sf170089

Hey guys. So, we seem to be having a problem with our 2001 Honda Civic, LX (160,000 miles). This is the car my wife drives to work. About a week ago, she said that she smelled a faint odor of gasoline. In particular, when the car was stopped. I drove it over the past few days and I could not smell anything. But, she has a pretty good sense of smell, so I trust her. Today, she drove to work in the morning and everything was just fine. At 5 pm, I get a call and she says something is wrong. She started the car. It was a rough start and the car ran rough. She says it is "puttery" with some vibration in the steering wheel. She backed up and started to drive away from work with the same type of rough driving. After a tenth of a mile or so, the Check Engine light would come on, then turn off, then come on, and then turn off. She turned around and went back to the parking lot and turned it off. She said it did not smell very good. So, I leave work and finally get there after about an hour. I start the car and it fires right up. I still cannot smell anything. I drive it around the parking lot and it drives perfectly. After some discussion, she drives the Civic home (~ 5 miles) and I follow behind. There are no problems. I cannot seem to replicate the problem.

Oddly enough, I saw jwall1689's 2001 civic LX Disaster thread: https://www.civicforums.com/forums/1...ard-start.html

It sounds like we are on our way to this type of thing. As RIPSAW mentioned, jwall is rebuilding his Civic one OEM part at a time. Perhaps I will do the same with our 2001 Civic, but I am hoping someone out there has a good first step.

My initial thought is fuel pump. Upon turning the key to the first position, I hear the pump turn on just fine. But, I am wondering if it is "losing prime." By the time I got there, she had already "re-primed" the pump and everything worked for me. Not sure if it is even possible. Just like jwall, I can try replacing that and the fuel filter to see what happens.

Let me know what you guys think.

Thanks!!

ezone

Check engine light was on and flashing. What code(s) does it have stored?


Is the smell raw gasoline, or raw exhaust? (knowing which it is will make a big difference in where to look)

sf170089

eZone. Thank you very much for your quick response!

It does not "look" like any codes are stored. I do not have an OBD scanner. So, I jumped pins 4 and 9 with a paperclip and then turned the car on to the first position (just power, no start). The check engine light did not flash. It stayed solid. Starting the car without the 4-9 jump, the check engine light came on as usual and then turned off. It has been sitting in the garage for about 5 hours, since we got home, and it fired up just fine.


Personally, I do not smell anything. My wife initially described it as "gasoline." After speaking to her again, it might really be exhaust. She said it kind of smelled like she was sitting behind a truck.


I am sorry to be so vague.

Thanks again!

ezone

"Raw exhaust" smell:
When the engine is started up cold, listen for rapid snapping noise from the exhaust manifold, usually more obvious during acceleration and quieter during deceleration (blipping the throttle is usually enough to hear this)....and noise subsides after a short while as things get heated up.
Leaking exhaust from (usually cracks) the manifold is not uncommon at high mileage. Again, this is usually much more noticeable while the manifold and engine are cold.

Also check for loose sparkplugs.

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If the flashing check engine light was blinking about once per second when it did it, that should indicate a misfire was detected. Hard code may not be stored if the issue was very brief.....
Might need to be able to read codes while the issue is present, and the simplest code readers are darn cheap these days. Seems like people have said you can get a dongle and a phone app for about 15 bucks.
More money gets you more capabilities.

HTH

sf170089

eZone, you are awesome! I think that is exactly the problem. Just above the oxygen sensor, there is a very thin, hairline crack in the exhaust manifold. I searched around and it seems to be in the same place as everyone else's crack (hmmm, that sounds weird). I watched some videos and read some posts and it seems like a really straight forward and easy job to replace.

Hopefully I do not offend anyone with my next question. But, looking up the price for a new exhaust manifold, they range from about $300 - $500 (big hit to our wallet). I am leaning towards the least expensive option, so I will go for the $300 end. Alternatively, I have seen people take the manifold to a machine shop for welding ($15 - $20 and 10 minutes of work) or even the car to a muffler shop and they weld it right then and there. Is welding an acceptable fix for the crack, or is completely frowned upon? I love working on The Civic, but a $20 weld and 30 minutes of time sounds a lot better than $350 and a few hours of time. It is more the money than the time. For some odd reason, we are lacking in the money portion of it.

Done. Thanks! Everything seemed good.

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This makes sense and sounds like what happened. She said that the CEL was really going on and off during the rough ride, so I am okay with codes not being stored. Since then, the car has run completely normally. She still smells the exhaust (I still do not), but the car runs great. The code reader app is a great suggestion and sounds a lot better than the $80 - $120 readers. But, I am embarrassed to say, we still have our same flip phones from 10 years ago :-(. So, I cannot get the app at this point.

Thank you very much for solving my problem, but I am hoping you can answer a few last questions. My main fear is that the crack has been there for a long time and it really is not the cause of the rough ride. Thus, after spending the $350 to fix it, she still has problems. Does a crack in the manifold lead to the rough start and rough ride she had on Tuesday? Being so close to the O2 sensor, I can rationalize it by a bad air/fuel mixture (i.e. too much air, not enough fuel). But, does that seem possible? As mentioned above, it ran great before Tuesday afternoon and it has run great since then. It was just that one time.

Thank you so much again for all of the help you have provided!!

ezone

Search online, check out local parts stores, Sears, Walmart etc. for OBD2 code readers. Still dirt cheap for the most basic of basic readers.

Flashing CEL while driving means misfire code (of some sort). Knowing the exact code helps eliminate up to 3 out of 4 possible cylinders
Cracked manifold alone won't cause misfire codes.

A low price to DIY attempt sealing up a crack is a no-brainer IMO....if it helps- you gained some time, but if not- you're only out a few bucks.
Many people just ignore the leaks and noise and put up with it OR don't even understand it's a problem (appliance users)

Misfire issue needs solved before replacing a cat, because bad running can ruin a cat, even a brand new one. If it runs bad enough or overfuels enough, you can ruin a cat in a matter of seconds. (can't tell you if you should pursue anything until it acts up again...I would probably keep driving and see what happens in the near future)


"rough ride" to me means something very different from "engine runs rough"
"rough ride" makes me imagine square tires......

sf170089

I took your advice. Sears has one on sale for $40.

http://www.sears.com/craftsman-obd2-...1&blockType=G1

I also had a $5 coupon and it got 4.5 stars. So, I figured it was a good deal.



:-) indeed.