Rep Power: 812

Ever since the new cylinder head went on, my idle has been really bad. The whole car shakes back and forth before I accelerate. I think it's due to the higher compression, but what can I do to try and fix it? I have a cam gear but don't know how to install it. Plus I don't want to make things worse adjusting it. So what else can I do to try and make it better? Thanks.

 
Rep Power: 0

don't you have VAFCII? I guess you can go to dyno tune your car...I bet your air/fuel ratio are off...

btw...my AEM CamGear works fine for me, but you gotta remove the cover for the cam gear...do you have a regrind cam? if not, then I guess by adjusting the cam degree doesn't work as nice as a regrind cam(I don't have it either)...

 
Rep Power: 812

So would just the air/fuel cause the idle problem? I have stock cam and stock cam gear.

 
Rep Power: 414

Sounds like timing is off or a vacuum leak...

 
Rep Power: 812

Hmmm. But it starts up perfect now and runs great. Only thing is once I let off the brake in drive (from a stop), I get the jerking back and forth before stepping on the gas. It's Kinda like pumping the pedal. So I think timing is fine, but how would I find out for sure? vacuum leak?

I'm also gonna spray some TB cleaner just in case.

 
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Since you had the head off, the timing belt be may a tooth off.

 
Rep Power: 812

It's still shaking pretty bad in drive while at idle. Then I press the gas and it's fine. How can I make sure the timing is right on? Also, would not enough fuel cause anything?

 
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My moms altima had that problem and when they fixed it they replaced the whole head. So i dunno could the head be bad. I dunno if that was the only problem to fix it but it had the same problem, the engine kept shaking in park

 
Rep Power: 812

Well this shakes when the car is in drive and I let off the brake. So it's just barely moving forward by itself. Then it shakes alot.

Don't know if this matters, but I was driving it hard yesterday and I noticed it completely went away for the moment. Then today it's back again. Really confusing. What else would cause it? Maybe if it's not gonna cause anything bad, I just won't worry about it. I'm scared to go to the dealer cause they'll take one look at my intake and header and say that's what's wrong. Thanks for the replies--keep em coming

 
Rep Power: 812

Bump. Anyone else? I looked at the cam degree kit and it's way too complicated. I wonder if the dealer would be able to see if the timing is off. Don't even know if that's the cause. Would rough idle happen from the air/fuel being off? sparkplugs?

 
Rep Power: 303

First: Check compression on each cylinder. That'll tell a lot more.

Check it both cold, and hot. Write it down and post the results.

 
Rep Power: 303

Gearbox, I have been following your troubles for quite some time on this board. I have been rebuilding engines for quite some time. There are basic rules to this game, and you have to eliminate the causes for this in a systematic order. Tough to do on a forum.
But I'll keep an eye on this thread if I can help.

 
Rep Power: 812

Well I don't know much about this stuff. How do I check compression? I'm assuming a shop can do this test, but those are slim to none in this small town.

I had an idea to change my iridium ngk with regular copper to see if it helps.

 
Rep Power: 0

ok since we can not adjust the ignition timing on the 7thgen that is not the problem. maybe you should check the spark plugs to see if they are fouled. Find the person(s) that installed the head and make them double check the cam timing. if it is off then that could very well be causing your problem. your compression should be fine, but then again you never know. you can get a compression tester from any parts store. you will want the one with the long hose and screw fitting. then follow directions it is very easy. if that comes out ok then maybe you got a bad head job. hope you find the problem. good luck

 
Rep Power: 812

Thanks. Is it easy to check the cam timing to make sure it's correct, or should I just take it to the dealer. I'll look into checking the compression. Thanks guys.

 
Rep Power: 0

When u put the head on did u line the timing mark up that was behind the crank pulley? If u did not that might be your answer. The one on the head is easy to set but the one on the bottom is hard. U have to take the engine mount,timing cover and the crank pulley off. If u need help let me know. I just got done puting my head on and setting my timing. I am just waiting for my tb now.

 
Rep Power: 303

You would need a compression gauge. You can get this at most autozone or stores like that. The civic needs one with a threaded hose to reach down into the sparkplug holes.
Or... you can have someone do it for you. Make sure the compression is even all the way across before you guess at what else may be wrong. Having the timing belt off by one tooth should not make it shake, but it would have less or a little more power, depends on the direction it's off. Do check the plugs, though. I had a new plug just be bad. That was weird, but it happened. The car shook. They were platinum plugs, and replacing the dud fixed it. You never know, I suppose.

 
Rep Power: 0

Could it be a leak??? I had a leak when I changed out my IM and it was due to the gasket not making a good seal...Does the RPM go up and down???

 
Rep Power: 812

Interesting. I just bought regular ngk v-power plugs to replace the iridium, just in case. I remember someone else said his timing was 1/2 tooth off and the car wouldn't even start. Mine is starting up and driving like new. It's just at idle where it shakes back and forth. All gaskets were new, and the install guys did a REALLY good job of cleaning everything. I doubt it's a leak, although that might be hard to know for sure if it's an air leak from the IM.

 
Rep Power: 303

Shaking could be caused by a leak, but it can be the valves as well. If one is not seating right, it will shake at idle but run fine at speed. That's why I recomend a compression test to rule out the head. Once you know the internals are ok on all 4, you move to leaks, flakey coil(s), timing, TPS, etc. Could even be a flaky injector.

 
Rep Power: 303

BTW, if the timing is half a tooth off and the car won't start.... why do they make adjustable timing gears???

(sigh)

 
Rep Power: 812

Good points. I'm gonna try the plugs tomorrow and then start on the harder stuff like compression. I hope it's not the valves or anything. Also, the vafcII is only putting in more fuel at wide throttle the way it's setup now. Would a lean condition at idle cause the shaking? I still need to get that vafc tuned sometime. I wonder if there's a way to measure air/fuel ratio, because I've heard bad things happen when the mixture is too rich or too lean. The little gauges they sell are worthless imo.

 
Rep Power: 812

Okay new NGK v-power copper plugs are installed. Still no change, and they felt almost the same as iridium. So another lesson learned. The v-power says it has a groove in the center electrode for reduced voltage requirements and quicker starts. So maybe they're even better than iridiums. Anyways, the iridiums all had this greenish coating on the tip, and I'm almost positive that's from the fuel injector cleaner (greased lightning). So I won't be using that anymore.

But yeah, the car still shakes with new plugs. So next up is compression. The cam gear also makes some clunk noise before the car is fully warmed up. Now just so you know, the car is still running fine. If I hold the brake down when at idle, you can barely feel any shaking. So maybe it's not as bad as it seems. Or the timing is a little off. How much does 1 tooth off translate to in degrees. Seems like it would be alot, and enough to maybe cause problems.

The car also needs tuning really bad. There are spots all over the curve that need more or less fuel added. I'm gonna try and find someplace that can dyno tune it for sure. But is there an easy way to just measure air/fuel while driving? I don't thing those blinking light gauges are very accurate.

 
Rep Power: 303

Well, once you check compression, you'll know if one of the valves is adjusted a little too tight or not. If compression checks out, go back and turn the engine to top dead center and check that all the marks line up. Then, it's tuning. Yes it could shake being too lean. Remeber though, that with the ports hogged out, you COULD just be getting some shaking due to the lack of backpressure which the engine needs. Those are trade-offs between more power and smooth idle. Regardless, you should follow a logical sequence to check the engine to make sure everything is in order.

 
Rep Power: 303

BTW, an Air/fuel gauge is better than nothing when you are trying to tune your mixture. It should get you in the ballpark, since it reads the O2 sensor directly.

 
Rep Power: 812

Thanks for all your help. I know I'm losing backpressure from the rear section exhaust. I was gonna try and put steel wool around the inner pipe to lessen the opening. Might be a bad idea though. But I'll try some of the things you mentioned and look for an a/f gauge.

Also, is it easy to replace the fuel filter? The service says every 15k, and I have 24k miles. Maybe that's why gas mileage is bad. Also O2 sensor. When does that need replacing? Thanks.

 
Rep Power: 812

They have digital and also modded autometer ones. Pretty expensive...

http://www.gadgetseller.com/gauges/order.htm

 
Rep Power: 303

Don't put steel wool in the exhaust. Steel wool can ignite. Try it on a small pad with a match. Make sure you have it on something non-flammable. It burns, like an ember, and then breaks down. Bad idea for an exhaust.

My last fuel filter lasted over 100,000 miles. They just don't get dirty that fast unless you fill up at some run down gas station that gets fresh gas once a year. Besides, a clogged fuel filter will starve the engine ONLY at high speed/load. It'll idle and run just fine around town. If the engine boggs down at WOT, but recovers when you ease off the gas, the filter needs changing.

O2 sensor can go bad from a problem like carbon fouling, or die in a week. It can also last 10 Years. Basically, the ECU will let you know if the O2 sensor is bad. The gauges basically just measure a small voltage generated by the O2 sensor, so you COULD tap a digital volt meter into the line just for diagnostic purposes to make sure the voltage CHANGES. If it does not, the sensor is bad.

As to your other question regarding the engine light, it SHOULD throw a code if there's even a slight problem. So the question makes sense, given your troubles.
The OBDII system has sooo many codes. If you don't get a code, it may mean that the ecu is still working the engine within base parameters. That does not mean that it is running "smooth", though. These cars are tough to diagnose, because the ECU uses fuzzy logic and is very adaptive. It will attempt to keep the engine running, no matter what. Anyhow, I have the 01-03 civic service manual in front of me, so if you need something, ask.

 
Rep Power: 812

So if the timing, a/f, or other settings are off, then the cel should come on? According to Honda, there's no problem if the light is off.

 
Rep Power: 303

If they are off TOO MUCH, the cel will come on.