gts

Just wondering if there is a Intake Manifold removal / EGR passage cleaning DIY? (fwiw I've looked but haven't found one)

Can the intake manifold be taken off with the TB intact or does the TB need to come off in order to get the intake manifold off?

Also curious what gaskets will be needed. I'd like to have everything in place for reassembly before I start taking things apart.

Also asking as many threads I've read seem to imply people have re-used all the gaskets after pulling off their intake manifold and TB. Maybe I misread this....

ezone

1.7L engine?

I don't have a DIY handy, sorry.

When I do it, I do not remove the TB from the manifold. I remove the entire assembly in as big a chunk as I can.

I reuse the gaskets (because we never have any in stock when I have to do this job).

Really, I can usually do the entire job without needing any parts. Just tools and time. (and maybe a little coolant)

Pay attention to how the plastic intake manifold and the fuel injector manifold (EGR distribution plate) are assembled. (this can probably be seen in a parts catalog diagram)
A couple of the fasteners do not go all the way into the head, they just hold the two manifolds together.

gts

Thanks for the insights
Yes it's a 1.7 Engine (D17A2)

Ok on the plastic intake manifold and the fuel injector manifold (EGR distribution plate) assembly, I'll take a look at the catalog diagram again.

I've estimated a 4 hours for the project including time for cleaning the EGR Passages.
Does this sound about right?

Not that it makes that much difference but I'll be doing the work in my driveway (my old school model-t garage isn't big enough for the car).

ezone

You're gonna need to get under it too...There's like three 10mm nuts holding the bottom of the manifold to some support brackets.

Once you get it apart and find the passages in the manifold, you should check the intake ports in the head you will probably find more carbon you can remove there too.


IDK about a first timer time target.....4 hours should be doable IMO.
I would guess around 2 hours in a shop.


Found some pics, first one may have originated in a thread here that seemed full of blanks on my laptop








Oh hell, this is one I took while the cylinder head was off




And if you check this top gasket in this pic, the small holes (yellow color) next to each intake port are where the EGR flows through from the distribution channels into the intake ports. There should be carbon in the ports where those small holes go.


The bottom gasket is for a non-egr application.

gts

Thanks again. Always good to see a few more pics (I saw few others during my research too).
The one you posted (before the gasket pics) is a nice big hi res pic. Really gives one a good look; you see a lot.
It's kind of funny how it's reflecting the color of the shop towels making it look pink.

For the life of me I didn't realize the intake manifold was actually "plastic".
Just took another (closer) look inside my engine compartment.
Yep that thing isn't black because it's "dirty"; it's the color of the plastic!

Depending on how the weather looks I hope to get to it on Sunday.

Would getting a Haynes or Chilton Manual be of any value for doing this project?

ezone

That depends on your skills, needs, and comfort level.

I personally haven't seen a Chiltons since I learned to hate them in the '80s. ("Remove part. Reinstall in reverse order of removal." Not very helpful most of the time for me.)


This thread may help: https://www.civicforums.com/forums/182-7th-generation-civic/235295-looking-7th-gen-manual-free-updated.html

Start on the very last page for the most recent links. You may have to sift through info to find what will apply to your car. (I know there are links to manuals for non-US markets, but many still use the same stuff ours do.)

gts

Thanks on the Manuals.
I downloaded one and found some pics that were a bit of help. Nothing specific about getting the manifold off but that was ok.

----

Couldn't work on it over the weekend and it snowed yesterday so...

Got it apart most of the way this afternoon.
Not hard at all except I'm somewhat stuck getting the mounting brackets off - the two underneath the Manifold that hold it in place.

I managed to get the 10mm nuts that hold the bracket to the Intake Manifold off but the Manifold still needs more room to back off the studs. This means getting the bolts off that hold the brackets in place.

There's not much room to move around under there. In fact I'm having a hard time finding a position where I can get a socket onto the bracket bolts and also have room to move the socket wrench and/ or breaker bar.

Also wondering what size the head is on these bolts. They are pretty rusted. I've scraped off what rust I can so a socket fits but even so I'm not sure what size the head is supposed to be.
Is it a 12mm?

Kind of frustrating to have the manifold so close to being off but have these three bolts holding me up. ;-)

Any help/ insight would be appreciated.

ezone

I can't see what you are dealing with under there and it's been a while since I had to take off a manifold by itself. Is the axle in the way?
Got an offset wrench?

Bolt heads on the block are probably all 12mm wrench size. (98% of the car originally used 8, 10, 12, 14, 17, and 19mm wrench sizes.)

You might be able to loosen the bolts several turns so the brackets have room to rock back as you push the manifold away from the head.

gts

Yeah the axle is in the way.

Unfortunately I don't have any offset wrenches (well none that are metric) but it'd be easy enough to buy one if it'll help to get off/ loosen the bolts that are holding the brackets on.

Thanks, I suspected the bolt heads were 12mm but the rust build up on them was creating some doubt. Last thing I want is to strip the head on any of them.

I agree, if I can get these bolts backed off a few turns there will be enough play in the bracket to get the manifold off. The trick will be finding a way to get them started to loosen/ back off.

guitarsnlikker

FWIW, I did the job myself and it wasn't that bad, and believe me I am strictly an amateur. My only problem was that when I put it all back together, I had a small leak so my idling rpm was off. I took it apart and retightened everything well and no more problems. I do recall that you dont need to take all three of the bolts off to release the manifold from the block. I think all you need to do is the center one, but verify that. The injectors just pull out on the rail easy. There is a YT video of a guy doing it and it was my starting point. That is
good luck.

gts

Got it done. Thanks for all the help ezone.
It wasn't all that hard.
Mostly inconvenient due to working on it in the driveway, cold weather etc...

Unfortunately I'm still getting misfire codes.
I read that epic thread you had with fsckewe and found a post where you suggest unplugging the EGR Valve and driving to see if the misfire codes go away.
That probably wouldn't mean anything now as I assume the misfire codes have nothing to do with the EGR passage being dirty.

Fwiw this is the big picture/ story.

Had a P0302 Cylinder 2 Misfire code.
(So the car wouldn't pass inspection.)
The CEL would come on, go off, be solid or would flash. When where or why didn't make any sense.

Changed the spark plugs (new NGKs') nothing changed.
Checked the coils with a spark tester (HEI) all sparked fine.
Did a valve adjustment. The intake valves on Cylinder 2 were a little tight and thought the adjustment might have cleared the issue.

The valve adjustment seemed to help but afterwards I got misfire codes on Cyl 1,2, and 4 as well as the one for the ELD! wtf?!

Replaced the ELD and that code went away.
But Cyl 1,2 and 4 remained.
I've cleared the codes a few times due to disconnecting the battery when working on the car and or with the scanner.
When they come back sometimes it only shows Cyl 2 and 4 misfiring.

What's odd (well odd to me) is after clearing the codes the CEL is off (as one would expect) while driving for the first time the CEL would come go on and off intermittently.
It would flash, then go off, then on and flash, then off again.
It seemed to go off based on rpm. at first it would go off after about 2k. Then it'd go off at about 3k and above.

After this initial drive and turning the car off then starting it up again the CEL would be on and solid.
Give it gas/ accelerate and it starts to flash but the flashing stops at 3k and above.
It did this consistently for a couple of weeks or so after the valve adjustment and before I started the EGR passage cleaning. Sometimes it would flash at idle.
Other times only after accelerating from idle then going off at about 3k. Back to idle and it would be solid.
Accelerate, it flashes then stops flashing at about 3k and becomes solid.

After removing and cleaning the EGR ports I'm now stuck with codes
P0302 Cyl 2 Misfire
P0304 Cyl 4 Misfire
P0300 Random Multiple Cyl Misfires

Fwiw when I had the intake manifold off I also cleaned the Throttle body as well as the IAC Valve.
I also cleaned the PCV valve and the EGR Valve (the EGR was done when I did the valve adjustment.)
I tested the resistance on the injectors and all read 10.8 ohms.
I connected some wires with alligator clips to each injector and attached one clip to the positive of the battery.
I then touched and released the other clip to the negative terminal of the battery see if the injectors would "click" on and off.
Each one clicked on and off as expected. No fuel sprayed from any of the injectors.
(I though it might as each injector was still attached to the fuel rail)

Going back a while at one point the car would randomly bog down at about 3800-4k rpm.
Never could tell when it would do this. Sometimes it would be just fine.
After the valve adjustment it stopped doing this. In fact it ran great except at idle.
Sometimes it'd stall at idle. But I could accelerate well over 5-6 k with no issue.
And the CEL would be solid at idle, flash between 1-3k and stop flashing / be solid at anything above 3200.

After the EGR cleaning and putting everything back together it acted the same way as above.
I warmed it up and took it down the highway about 10-12 miles.
It was running great and above 3k the CEL would go off (or stay solid when I stopped then restarted the car and ran the rpm above 3k).

I then threw about 3-4oz of Seafoam in the gas tank. Tank was at about 1/8 full and drove it.
Filled up the gas about 7-8 miles later. Drove it about 140 miles last night, a combination of state highway and interstate highway miles.
It was bogging down consistently at 3800 rmp. Could the seafoam have caused this bogging down?


I haven't done a compression test (not sure of the procedure though I do have a compression gauge).

I also plan to buy a set of Noid lights to check the injector electrical connections.

In any case I need to figure out what's going on.
Is there anything else I can do/ test to try and sort out why the Cyl 2 and 4 misfires are happening?

ezone

Unplugging the EGR valve is a diagnostic step, I would have done that long before just diving in and taking anything apart.

------------------------------------------------------------------


Make sure oil is full.....You seem to say it has been consistently doing something odd while driving at certain RPMs...let me run with that thought for a minute:

If the car is sitting still and you hold the engine revs at that RPM does it still do anything wrong you can feel?

If so,
Operate the throttle by hand in the engine compartment....
Hold it steady at that RPM where it's obvious something is wrong and keep it there, now...one at a time, gently touch and/or wiggle wires for the fuel injectors. See/feel/listen for improvement when you touch wires. Note which one(s) causes a change.

OR, conversely, if it didn't act up while sitting still, hold it at the exact RPM you expect it to do something wrong, gently wiggle wires and listen for the problem to act up.

NOTE: Gently, I'm thinking don't wiggle or move much more than natural engine vibrations and driving would cause anything to move. If you bend and fold wires to new positions, you may cover up or hide the problem for a while, only to have it return later on.


Same for coil wiring, gently wiggle those too.

Reasoning: "If a terminal gets spread wider than it is supposed to be, it may cause an intermittent connection."
Female electrical terminals may lose tension over time and miles, engine vibrations and harmonics may cause them to break their connection briefly..(just like an old wall outlet in your house that can't grip and hold a plug anymore, may lose connection if you wiggle the plug)



================================

Also...search 'terminal tension test' (https://weber.instructure.com/course...ension-testing)

I have a couple sets of these for checking electrical terminal tension, plus many male terminals scrounged from various wiring projects that come in handy for the purpose:



Since you have a compression gauge, you may still want to do the compression test.....but unless it sets misfire codes at idle consistently I'd not suspect this test to uncover big problems.

I'd skip the noid lights right now, I don't see that helping find an intermittent problem. If you had, say, an injector not firing at all causing a dead hole, noids may help answer the "is the injector being triggered or not" question.




If you think you have an injector problem, swap the suspect injector with one from a good cylinder and see if the misfire code moves (follows the suspect injector).

gts

Ya know I just remembered something that your latest suggestions brought back to mind.

Before testing the coils I swapped a couple just to see if there would be a change. Nothing happened.
After getting the HEI spark tester and finding spark on each coil I did this swap again. Once again nothing changed.
I didn't expect there would be a change as all four coils were delivering a spark with the tester.

About two or three weeks ago with the car running I pulled the connector on each coil.
Pulling the connector on the coil for #2 nothing happened, no audible change like it did with the other coils.
It seemed the same for#4 and #1 too. On #3 the change was very noticeable.

I just went outside and did it again on #2. Same thing nothing audible.
I couldn't quite tell on #4 (there was a change but it seemed subtle).
On 3 and 1 there was an obvious audible change.

The culprit(s) may have been found.

Is there another way to test these connectors?
Would using a DMM on any of the three terminals inside the connector reveal anything?
If so what would I do to test them with a DMM?

Also is the coil wire harness replaceable (if that would be the fix)?

ezone

You have only identified weak or dead, non-contributing cylinders. (Meaning, you haven't proven an ignition problem. If there were spark but no fuel for that cylinder, it would still be dead.)

You still need to figure out why.


Raise the RPM to ....steady 3000 RPM or so and repeat that check, unplugging each coil for a couple seconds. Each one makes a difference now? That would tell me the coils are working.


So it's got at least one dead cylinder at idle.......Do the compression test?

gts

Makes sense. I stand corrected.

Just did this and it made a difference unplugging #2.
There was an obvious audible difference.
Checked the other three again as well and each had an obvious audible difference.

I'll try to do the compression test tomorrow.

Why would #2 be dead at idle but not at 3000 rpm?

ezone

Spark is not AWOL.


Do the compression test.

IF this is caused by low compression.......It has to do with the size of a (compression) leak and the speed of the piston. Size of leak vs. volume.

Small amount of leakage may cause significant compression loss at low RPM, but higher RPM may not allow sufficient time for the leakage to make a big difference.


Another example might be, a vacuum leak at the intake manifold gasket/fuel injector area can disrupt the fuel delivery and cause a single cylinder to be lean enough to misfire at low RPM, but fire ok at higher RPM.

gts

I greatly appreciate the explanations and insights.
I enjoy learning how/ why things work.
While the EGR passage cleaning etc may not have been necessary I learned a lot.

That said......

The compression test showed a great disparity between the Cylinders.

Cyl 1 = 225
Cyl 2 = 55
Cyl 3 = 215
Cyl 4 = 75

I let the car warm up at idle for about 15-20 minutes.
Then drove it 1/2 mile to where my tools are located and did the test.
Tested each Cylinder with the throttle wide open aka accelerator pedal floored.
Also tested each without touching the accelerator. No difference in the numbers.
Lastly each Cylinder was tested multiple times (4+) and the numbers were consistent.

Fwiw there was an audible difference when testing Cylinders 2 and 4 as compared to 1 and 3.

The car has been burning oil but I've never see smoke coming out of the exhaust pipe.
I haven't any specific data on how much it goes through (miles per quart) but I have to add a quart or two every few weeks over the past year or so.

Most of my driving is short trips around town with the occasional 30-40 mile round trip thrown in here and there.
There are the few 80-100+ mile round trips about 3-4 times a month.

ezone

That's not good.

Next step: verify valve lash adjustment and correct if necessary. If valves were too tight and you adjusted them, do another compression test to see if the low ones come up.

If compression is still low after valve adjustment......The next step would be cylinder leakdown testing, to figure out where the leakage is.

gts

I was reflecting on the previous valve adjustment I did and wondering if I screwed it up.
Seems plausible considering the misfire codes went from just Cyl 2 before to Cyl 1, 2, and 4 afterwards.
Could have swore I did it correctly but perhaps not.
Will redo as soon as possible. Unfortunately the cold and snow is having an impact on my ability to get to it.

Considering the cold (20's- 30's), how long should the engine sit before doing a valve adjustment?
In other words is there a temperature one can take on some part of the engine (or perhaps the oil or coolant) to know it's cool enough to do the adjustment?
I've read let it sit overnight, but overnight in 70 degree temps is a little different than overnight with temps in the teens and 20's.


On a personal note; what's the Tony Alva Skateboard in your sig about?
I haven't seen or heard his name since the mid to late 70's!

ezone

Head and valves need to be cold.
I believe the FSM just says something like the engine should be 'below 100*F'. I think that will be easy for you to attain rather quickly LOL.
If you have a way to read the engine coolant temp sensor, that works.
If not, use your senses.
You're gonna have the valve cover off to do the work so take it off first, wait a while, then surely you can tell by feel if the cylinder head is well below 100*F.

In the shop .....the idiots at the write up desk tell people they can wait while we do this sort of work----yeah right, LOL.....so I might take the valve cover off then set a fan blowing on the top of the engine and go to lunch or something..... even in the summer it cools down in a reasonable time, maybe an hour before it "FEELS" ok to the touch.


I bought it/built it new in 77 and still have it.
Click the links in the sidebar to see it and the other vehicles in 'my garage'

gts

Just read the Service Manual/ instructions for the valve adjustment and now think I may have screwed up the previous attempt.
Ugh! If so hoping it hasn't caused any further damage.

Fwiw I followed the DIY on the forum
As well as the instruction in this video:
The only difference was I didn't take the pulley cover off.

I found TDC for Cyl 1 by lining up the V indexing slot with the yellow mark on the harmonic balancer (that's what the guy in the video calls it).
From there I lined up the two notches on the camshaft gear with the top of the head - rotating them 90 degrees for each of the Cylinders.
Does this sound right?

Hoping to do the valve adjustment again tomorrow as the weather will have 'warmed up' from the frigid temps of the past few days.

------------

Pretty cool on the Tony Alva board! I made a few boards from scratch back in the day.
I even built a half pipe for a local skateboard park owner. Have some old 8mm video/ film (somewhere in the 'archives') of friends skating on it.

ezone

I don't either. I can figure out where the intended cylinders' lobes are by watching for overlap to occur on the companion cylinder.
I dunno.
Got a real service manual you can refer to?

gts

I have a 2001 service manual (a pdf file found online referenced from your post #6 in this thread).

I can't seem to figure out which section in that manual has the valve adjustment procedure. I'll keep looking.

thetut

If it's the file I think it is, the adjustment procedure start at section 6 - 14.

gts

Yes that was it. Thanks.

gts

Things have gone from bad to worse.
Adjusted the valves today without a problem.
But the bad to worse likely happened before the valve adjustment today.

Last Thursday night/ Friday morning sub zero temps moved in (-15 to -20 below with the wind chill).
I got a call to help a friend get home. She had been in the emergency room all night.
Started the Civic and drove it around the block a couple of times (easy) to get it warmed up before heading to the hospital which is only 1/2 mile away.
I wanted the car warm (heat on) when I picked her up.
Drove her 15 miles to her house. Dropped her off and drove 15 miles back.

During this 30 mile round trip in the sub zero cold it was the same deal as has been going on.
CEL on when at idle.
When rpm is between 2k and 3k the CEL would flash. At 3.2k and above CEL is solid.
So when driving I'd keep it in a gear where the rpms would stay at about 3.2k (as much as is possible).

As things turned out I did not need to do anything that needed a car the rest of the day so it sat on Friday from about 7am on.
Saturday a snow storm (6") hit and cancelled just about everything for the day so the Civic continued to sit in the driveway.
Temps were still pretty cold but not the -15 to -20 as it was on Friday. Maybe hit 20 above zero. I didn't bother cleaning the snow off the Civic.

Sunday of all things a warm front moves in (50 degrees!) and it rains.
Much of the 6" that fell on Saturday melts. Late Sunday the rain clears out and the sun almost comes out at around 3pm.
I cleared the snow (what was left) off the Civic and drove about 1 mile to get some groceries.
It was struggling to run and sounded like it was bogged down heavily. During this short drive it stalled a number of times.
The stalling happened at stop signs and or when sitting at a red light.
Could something have gotten wet and maybe shorted out? It had never run so badly before.
Or could the sub zero temps have done something?
In any case I got it back to the house parked it and let it sit overnight.


Monday morning I started it up in the driveway and let it warm up for about 10 minutes. Seemed to be running "ok" during the warm up.
Backed out of the driveway and pulled up to the stop sign (all of about 40 feet).
As I tried to pull out/ accelerate from the stop sign it bogged down and almost died. I had to rev the engine a number of times to keep it from stalling.
Got out on the street but it wouldn't accelerate at all. I did all I could just to keep it running.
At one point I managed to get it up to 25mph but on the slightest of an incline it struggled, really struggled. It was so bad I put the emergency flashers on.
The more I gave it gas the more it wanted to stall. Even when gently/ gradually pushing the accelerator.
I decided it's not going to make it anywhere and turned around, drove it 3/4 mile to where it sat until today.

I tried starting it today and it ran real rough. I'd put it in gear and as soon as I backed off the clutch it would die.
In neutral I couldn't get the engine above more than 3-4k rpm (even getting it to run well enough/ long enough to be able to try to get it to 3-4k was a struggle).
As soon as there was any load on the engine (re: putting it into gear and letting out the clutch) it would die.
It got to the point where it was turning over and over struggling to start.
In fact 80% of the time it wouldn't start and when it did start/ run it would die within a few seconds.

I said screw it and did the valve adjustment anyway.
I adjusted them all to be sure all were good but they really weren't out of adjustment from the adjustment I did a few weeks ago.

I tried starting it up after the adjustment and it was the same as this morning - ran rough and wanted to stall.
The CEL came on almost immediately after it started to run.
It was showing P0302, P0304, as well as P0300.
For the life of me I couldn't get it to run more than a minute or two. Finally it just wouldn't start at all.
It was like it was choking and couldn't breath.... or getting flooded.
It also sort of sounded like it might want to back fire if I kept pushing it, trying to get it to start/ run (if you know what that sort of thing sounds like).

At this point I may not be able to get it to run and warm up so I can do another Compression test on a warm engine.

So is the only thing left to to do at this point the Leak down test? See what shows up from that?

As for the leak down:
Can I hook the hose from my compressor directly to each cylinder and see what happens or do I have to have one of the Dual gauge Leak Down Tester configurations with a regulator?
There is a regulator on my compressor but my compressor is made for use with a nail gun and the like.
I do use it to blow saw dust off when working on cabinets and the compressor kicks in as needed but it wasn't made for blowing a constant stream of air.
Fwiw it will put out about 125-140psi

ezone

I'd say to start with the compression test, even with it cold we need to see the results you get.

Connect a charger to the battery so it doesn't get drained during testing?

ezone

WAIT a sec.....if your new compression test looks ANYTHING like the previous, move to the leakdown checking.



And hope the cat hasn't been damaged...if the substrate broke apart and is clogging up the exhaust, that's just more problems.

gts

Ok will do.

------
Fwiw my adventure into this started with a Cyl 2 misfire, nothing more.

A valve adjustment was suggested.
After the valve adjustment things got worse.
Oddly the car ran better but now there were misfires on Cyl 1, Cyl 2, and Cyl 4, as well as a code for a bad ELD!
Was this just a bizarre coincidence?

Replacing the ELD fixed that code.

Sometimes the Cyl 1 misfire goes away, but the misfires on Cyl 2 and 4 have been consistent since the first valve adjustment.

What baffles me is why after the initial valve adjustment did I start getting two more misfires as well as the ELD!

Based on where things are at now maybe it's a mute point but I'd really like to know/ understand how and why things got worse after that valve adjustment.

ezone

ELD is a known issue, there's a bulletin on them. Separate issue altogether.

Low compression on 2 and 4 should be the cause of misfire codes on 2 and 4.

(Misfire code on #1 could be a result of continued running while other misfires are going on. That's a pretty common occurrence.)

Valve adjust may have had no bearing on what happened next, because you continued running the engine and driving around with misfires and running poorly:

Bad running, rich running, and misfires can ruin the catalytic converter. Passing raw, unburned, or excessive fuel into the cat will overheat it and can cause the element (substrate) to melt or break apart and clog the exhaust and/or physically damage O2 sensor.


Even a brand new catalytic converter can be ruined in a matter of just seconds if the running conditions are bad enough.