Need help still!!

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10-04-2005, 09:20 AM
ITC007

Happy October to all,

I have a pretty much stock 1.5 in a 1991 civic, equiped with a header. I runn this in ITC thru the SCCA.
I posted before on a stumbling problem I have with the car.
I put the car on a mustang dyno at Wheel to Wheel in Michigan. Car starts up and idles real rich-9's and low 10's for A/F ratio. It runs in the high 10's and low 11's at WOT.
Question is, how can I lean this car out with stock parts and or what would cause this car to run that rich? :119:
Thanks in advance to any info!

Devin ( in need of help)
10-05-2005, 11:17 PM
Catch22

Thats a tough one. I have the exact same car and have never seen anything like that.

A few suggestions, and I'm just taking shots in the dark...
- Try a different ECU. My 91 came with a PM9 ECU but runs much better on a PM5 ECU from an 88 Standard. I don't know why, it just does.

- Check the injectors. One might be sticking open and just dumping fuel.

- Check the fuel pressure regulator. It might be stuck.
I suggest installing an adjustable regulator with a gauge. The Si regulator will fit if you flip it upside down and do a little grinding on it.
I actually run a pretty high pressure in my car. About 45psi. People always say "Thats too high" but the car runs great. The dual point injection is kind of an unexplored area, so who really knows whats too high and too low?

Thats about all I can think of right now.
Good luck with it, and bring it down south some time. The ARRC is the most fun you'll ever have at the track ;)
10-06-2005, 12:33 PM
ITC007

Quote:

Originally posted by Catch22@Oct 6 2005, 03:17 AM
Thats a tough one. I have the exact same car and have never seen anything like that.

A few suggestions, and I'm just taking shots in the dark...
- Try a different ECU. My 91 came with a PM9 ECU but runs much better on a PM5 ECU from an 88 Standard. I don't know why, it just does.

- Check the injectors. One might be sticking open and just dumping fuel.

- Check the fuel pressure regulator. It might be stuck.
I suggest installing an adjustable regulator with a gauge. The Si regulator will fit if you flip it upside down and do a little grinding on it.
I actually run a pretty high pressure in my car. About 45psi. People always say "Thats too high" but the car runs great. The dual point injection is kind of an unexplored area, so who really knows whats too high and too low?

Thats about all I can think of right now.
Good luck with it, and bring it down south some time. The ARRC is the most fun you'll ever have at the track ;)

[snapback]61896[/snapback]

Thanks for the info.

I would like to bring it down next year for the ARRC. I just want to have a good full season with the car running right. The car has ran like this since the last season. hopefully next year will be different. Thanks again and good luck at the ARRC.

Devin
#12 ITC Civic
10-14-2005, 06:24 PM
H5Civic

Quote:

Originally posted by ITC007@Oct 6 2005, 04:33 PM
Thanks for the info.

I would like to bring it down next year for the ARRC. I just want to have a good full season with the car running right. The car has ran like this since the last season. hopefully next year will be different. Thanks again and good luck at the ARRC.

Devin
#12 ITC Civic

[snapback]61950[/snapback]

Devin,

Did you change the dizzy and did it help w/ your "stumbling" problem? If not, please let me know, because I still have my problem, and since I haven't had mine on a dyno, it could be doing the same thing as yours and running that rich could be the issue.

Regards,

Sam
10-17-2005, 04:59 PM
ITC007

Quote:

Originally posted by H5Civic@Oct 14 2005, 10:24 PM
Devin,

Did you change the dizzy and did it help w/ your "stumbling" problem? If not, please let me know, because I still have my problem, and since I haven't had mine on a dyno, it could be doing the same thing as yours and running that rich could be the issue.

Regards,

Sam

[snapback]62708[/snapback]

I bought a brand new "not rebuilt" dizzy. Unfortunatly it did not help my problem.
I'm just totally lost. However I did get some good info that I will be trying thru the winter. I will post it.

Good luck,

Devin
10-17-2005, 05:03 PM
ITC007

at idel, on a stock map, honda's idel in the 14 to 16:1 range when warm. although it sounds bad, this is perfectly normal. (cold starts have a little different thing going on, so i'm not even going to get into that.)

if you're running rich on stock honda ecu, inejctors, and fuel pressure with no codes, it leads me to think something is clogged in the air flow path.

less air is actually getting in than what was accounted for, so your burn process runs rich. it happens through out the entire rpm band...

things to check:

02 sensor (but technically this should throw a code if its REALLY in the 9's as its out of the narrow band's voltage range of accuracy)

map sensor- check that the vacuum line isn't kiked, and that the port for the vac source isn't clogged or dirty.

dirty or misfiring injector. your car is old. if the injectors are stock, one could be failing and staying open too long. could also be a problem with your resistor box/wiring or the actual ecu. but these should throw codes...

check your timing. if your timing is off, everything is screwy. throw a light on there and make sure your base is around 16 degress advanced.

clogged cat. if the air can't get out fast enough, it will back-up and do wiered things. i wouldn't say it would make you run rich, but it could be a factor in the problem.

a very good posibility, is that the dyno's o2 meter is fucked up... but you do have a stumbling problem... so that's probably not the case.
wide band o2's don't last forever, and esp. if they see race/leaded fuel, they don't last long at all. have the dyno guy clean the o2 with a propane torch next time you go in. or, have a buddy with a known good running car do a couple pulls to validate the o2 (or just watch another customer's results)

I'd start with a simple can of injector cleaner in a tank a gas. run that through... see if it does anything. if not, $5 gone.. oh darn.

if that doesn't help, throw the imting light on it.. check your distributor marks, make sure you're at about 16* advanced at idel. if your idel is off or bouncing, it will be hard to get an accurate reading.

do a leak-down test. you might have a faulty valve or ring or something leaking in some crap and screwing up the mixture.

bleed your coolant system. you'd be suprised what an air pocket can do... coolant temp sensors can also be mis-leading. throw an ohm meter on that and get out your manual to see if its in the service limits.

check the tps. throw the ohm meter on it, and with a buddy in the car test it with key on, engine off, closed to wot voltage ranges. make sure its in the 0-5v spec.

Hope this helps, I will be doing all I can thru the winter.

Funny thing is, the car ran great for 1 weekend. I won every race, led all but 2 laps and was 1 tenth off the prev. track rec. set in 1999.
Then the next week it went right to hell again. <_<

Devin
10-17-2005, 10:01 PM
H5Civic

I'll have to check the airpath. Iceman CAIC doesn't seem to have a problem, though I could take it off and go up & down the road a few times to see what happens.

O2 could be a real problem, especially since if the car sits idling for more than 5 minutes it starts throwing an O2 sensor code.

Haven't looked into the MAP sensor yet, but will do that as well

Injectors were both just balanced and blueprinted by RC Engineering, so there isn't a problem there.

16 degrees advance actually wasn't enough, as I found that the more timing I threw at it, the better the car ran and the less it "stumbled". Right now the car is set at about 23 degrees advance.

There isn't a cat on the car, so that isn't the problem.

I need to get the car on a dyno to see where my numbers are and I can go from there. I'll let you know where I'm at once I get this done.

Engine had a complete rebuild last fall, and still sits at 120 oil pressure on cold start up and gets to 90-100 oil pressure when warm at WOT on the straights.

Flushed the coolant already several times this year, so no dice there.

TPS is a possibility, as all of the throttle bodies I've had have been used and I haven't tested the TPS to see if they are still good. Do you have a source for a known to be good TPS? I've been trying for months to get one w/ no luck.

Best of luck over the winter in finding your demons, and I'll let you know how I progress in my quest to conquer mine.

Sam
10-18-2005, 10:06 AM
ITC007

Quote:

Originally posted by H5Civic@Oct 18 2005, 02:01 AM
Do you have a source for a known to be good TPS? I've been trying for months to get one w/ no luck.

Sam

[snapback]62867[/snapback]

Some say that you can pull off the old ones and put a new one on. I would not do that, It just seems that they are very sensitive to how you put them in.
I'm kinda against the TPS theory, just because they are not that known to go bad, like say for instance the igniter! I think if you have changed your throttle body then you probably have a decent one in. I still have to get the injectors cleaned on my car, and I will be making a new air intake as wll as a few other things on that list to check. One of us will figure it out soon enough. I'll let you know if I have made considerable process.

Devin