v00tecsi

This just started happening yesterday. The car will run fine in the higher rpm range (3500+) but between 2-3k the car "feels" like its running extremely rich (the car sputters really bad and you can smell gas) Its really weird because it doesnt do it all the time, but when it does it sputters really bad until you get past 3-3500 rpm, then its runs ok???? The only issue the car has is that I DESTROYED my header on a man hole and its dented pretty badly. However, its been like that for about 1-2 months and the car has never done this. The only other thing I can think of is that it started after I got gas yesterday, but if it were bad gas, why would it only act like that in the low rpms?

My mods are Skunk2 stage 1 cams, gears, springs, etc...I'm running a Kenji chipped p-28 tuned by p1auto with a vafc. The car has been tuned and running excelent for over a year now, and non of the settings have been touched, so this is weirding me out.

I have not had a chance to pull any plugs, I also just ordered a new header from p1 and plan to have him look at the car after I put it on and put it on the dyno if necessesary to figure out the problem.

From what I explained can any of you guys think of what it could be?

Cliffs notes:

-Car running like its running really rich (sputtering badly) from 2-3500k rpm (but runs ok in the higher revs)

-only known mechanical issue is a dented (badly) header but its been like that for almost 2 months with no issues besides the car having lost some top end power)

-mods are stage 1 cams, p-28 chipped tuned with vafc (been tuned for over a year no problems)

Edit: Fuel preasure looks good according to the trusty gauge under the hood

Turbo E

impacts can damage a O2 sensor. my guess, it finally gave out or something internal is loose and periodically working. anyways. borrow another O2 and see if the prob goes away.

v00tecsi

I'll take a look under the car and look for any further damage near the 02. IF the 02 was bad wouldn't it throw a code? Even though I converted to obd-1 (p-28) I still thought a bad 02 would throw a code


Modified by v00tecsi at 3:00 AM 11/2/2004

v00tecsi

No one else can help me out here????

The problem seems to be getting worse and worse and it really makes no sense to me. 7/10 times the car starts normally and runs normal until about 10 minutes of driving. After that the car starts to idle like **** and you can smell gas. If you try to drive it from a stop the car shutters like a choked out lawn mower until you get above ~3500 rpm, then it pulls out of it. I know the header is crushed badly (just ordered the new one) but its been like that for ~2 months. If its the 02 then why am I not throwing a code and why is it only doing it sometimes and in the lower rpms?

Im gonna replace the plugs, but again even if the plugs are fouled, why would the car not act like this all the time and only when it's been running for some time?

Basically the car is in some way "flooding" itself out or out of know where running very rich (i think) in the lower rpms and idle after its been running for about 10 minutes)

Someone here please add something cause I'm lost

Jaydeep

DO you have check engine sine on? I got same problem man

When engine is cold does you car runs normal for 5-10 minuets? (when you start driving in the morning)

v00tecsi

no lights...

I just pulled the plugs:

Jaydeep

I want to know this too. So guys please help us.

Louie_EM1

What's your fuel pressure at?

ZacCarter

iTrader: (1)

That first ten minutes of when the car is started is when the ecu is on closed loop and not taking any readings off the o2 sensor because the car is not warm. It sounds like when it is switching over to open loop operation that it is trying to get input off the o2 and see's nothing. When the car gets into high rpm's the fuel curve gets to where it at stoich and doesnt have any problems. Fix your o2 its broke i think. Anybody else?

v00tecsi

Yeah after thinking/reading about this for two days that is the only thing that really makes sense. If it were a bad dist cap or a loose cam gear or something of that nature, the ca would be acting like this all the time, not just after 10 minutes. The only thing that threw me with the 02 is the fact that i did not throw a code, but that may be due to the fact that im running the keji chip.

I'm going to replace the 02 sensor and see if that fixes the problem.

Thank you, I'll update the thread after the install.

Redline96LX

Check both O2 sensor signals, and if your header is cracked, the lack in backpressure right there could **** up ****. Also, if you got build up, try sea foam. Also, run it on clean gas, like from Quicktrip. Its the cheapest, and the cleanest. My car runs best on it, with its top tier rating and ****.

Jaydeep

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ZacCarter &raquo;</TD></TR><TR><TD CLASS="quote">That first ten minutes of when the car is started is when the ecu is on closed loop and not taking any readings off the o2 sensor because the car is not warm. It sounds like when it is switching over to open loop operation that it is trying to get input off the o2 and see's nothing. When the car gets into high rpm's the fuel curve gets to where it at stoich and doesnt have any problems. Fix your o2 its broke i think. Anybody else?
</TD></TR></TABLE>

But if o2 is bad RPM keep on jumping. I had o2 bad in my BMW and thats what happed. So I don't think its o2.

v00tecsi

Im swapping out the 02 tomorrow so we'll see if that fixes it.

If thats not the problem, do you think it could be a bad coil?? Someone on another board said theirs went bad and the car was acting simular to mine (the fact that it takes 10 minutes to start doing it makes no sense though???)

Jaydeep

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by v00tecsi &raquo;</TD></TR><TR><TD CLASS="quote">Im swapping out the 02 tomorrow so we'll see if that fixes it.

If thats not the problem, do you think it could be a bad coil?? Someone on another board said theirs went bad and the car was acting simular to mine (the fact that it takes 10 minutes to start doing it makes no sense though???)</TD></TR></TABLE>

Did you check to see if your o2 was bad?

EKFerioHawaii

waiting for outcome....

Jaydeep

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EKFerioHawaii &raquo;</TD></TR><TR><TD CLASS="quote">waiting for outcome....</TD></TR></TABLE>

Do you have same problem?

OptimusPrimeX

Have you checked your exhaust and smelled it? .. does it seem like its running Extremely rich right when you start it up?..

are you getting more smoke then usual because of the rich condition?

Does the Car want to Stall out, and do you get a Check engine light?....


i would say

-Replace the O2, you'll know right away if its that when replaced
-check your spark plugs..you already pulled them i see from the pic. ... The middle plug looks a bit more "dirty" on the threads.. what is that?.
-check the settings on your VAFC?... if you mess with it yourself that is...
- Have you done a Compression test lately?....

v00tecsi

I am switching the 02 out tomrrow because my header came into p1 today and I figured I would do the header install and the 02 at the same time, so I will update you guys tomorrow on how it goes...

Like I said, the car seems to run fine when you first start it and continues to run normal until about 10 minutes of driving. Then the car begins to idle very bad and run extremely rich. You can smell it and the car shutters to the point where it almost stalls. I noticed when the last time I drove it (to get it in the garage from my apartment) that if you give it only a tiny bit of gas it wont shutter as bad, but when you give it enough to accelerate off a stop for normal driving it wants to stall out and like I said shutters real bad.

I am going to replace the plugs and dist. cap just to be safe. The vafc has not been touched sinse the day it was tuned almost a year ago. I have not done a compression test in a while but the last time I did it was good.

When I pick the header up tomorrow I am going to talk to Jack (owner of p1 auto and who tuned my car) and see what he thinks. I'm also going to switch out the 02 and see what happens. I'll let you guys know tomorrow how it all works out. If it's still not running right, were going to have to go back to the drawing board

Thank you all for you help, keep your fingers crossed.

v00tecsi

I switched out the 02 sensor and replaced the crushed header with a new one. Although the car does seem to be running better, it's still shuttering in the low rpms and basically doing the same thing, so its safe to say that it wasn't the 02 sensor. I also tried my stock ecu just to make sure it wasnt an ecu problem, but it wasn't.

I talked to Jack at p1auto (guy who did my tuning) and he said if it wasnt any of that, it may be a map sensor?? Its beyond what I can figure out now, so on Monday I'm dropping it off at p1auto and letting Jack figure it out. I'll keep you guys updated on what it is, because at this point were all dumb founded

Jaydeep

I knew thats not O2 because if O2 is bad RPM would jump up and down. + check engine light would be on.

Now I am thinking same thing. It is defiantly some sensor. If you want me to check that in my car I can do that by taking it out from my friend's car. We both have same problem so If I change map sensor and fix problem then go ahead and buy one. Because there is no point changing all parts that are good and send more money.

But can some one tell me where is MAP sensor is located at?

v00tecsi

also could this by any chance be a bad coil??? The thing thats weird and stumping all of us is the fact that the car runs normal until its warmed up???

E-brake or Handbrake

Replace your o2 sensor and check your cat to see if it's clogged. I think you're bottlenecking from your dented header. But checking your CAT won't hurt...


I recommend this because I'm in the same situation. Your cat is probably going to take a **** on you soon.

v00tecsi

Already replaced the 02 and I put the new header on it yesterday and it's still doing it. The cat is less then a year old and is a high flow. It may be shot but I don't think it would cause all of this even if it were, but I will check it anyway.

evilcivilian

Hey,

Here's my experience with the subject.

Me and my friend swapped in a jdm d15b into his dx d15b8. We decided to reuse the distributor and ecu.

The car ran like **** so we replaced the distributor and the ECU with the correct ones and it ran like a champ only at high RPM. Low RPM it sputters just like yours but minus the gas part. I decided to open the ECU and I found out that many things were soldered out and taken out of the ECU and then sold to me. I bought it from a honda-tech member by the name of Theo, going by dohcnotec. If you guys decide to buy him from take my word for it.. don't.

Now my suggestion for you is that it has something to do with your distributor, either cap or rotor. And I also remember reading a subject similiar to this where all the guy had to replace was his fuel filter. Have you changed your fuel filter for the past 30,000 miles? Its only like a 20 dollars replacement and its well worth it since it gets clogged up all the time. Well Keep us updated man.

Hopefully my advice can help.

Jaydeep

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by evilcivilian &raquo;</TD></TR><TR><TD CLASS="quote">Hey,

Here's my experience with the subject.

Me and my friend swapped in a jdm d15b into his dx d15b8. We decided to reuse the distributor and ecu.

The car ran like **** so we replaced the distributor and the ECU with the correct ones and it ran like a champ only at high RPM. Low RPM it sputters just like yours but minus the gas part. I decided to open the ECU and I found out that many things were soldered out and taken out of the ECU and then sold to me. I bought it from a honda-tech member by the name of Theo, going by dohcnotec. If you guys decide to buy him from take my word for it.. don't.

Now my suggestion for you is that it has something to do with your distributor, either cap or rotor. And I also remember reading a subject similiar to this where all the guy had to replace was his fuel filter. Have you changed your fuel filter for the past 30,000 miles? Its only like a 20 dollars replacement and its well worth it since it gets clogged up all the time. Well Keep us updated man.

Hopefully my advice can help.</TD></TR></TABLE>

I know its not ECU. Becaue I already swap that from my friends car.