MISSvvvvvvMISSvvMISSvvvvvv

[geno5.0]

My damn car is missing and I can't find out why! Ok here is the Problem. My car seems to be running well at WOT nothing missing very strong! but when I am cruzing between 2000and 3000 Rpms
I am getting a slight miss on one of the Cyl I cant figure it out! I have checked all the plugs over and over nothing wrong there. replaced the cap and Rotor all the plug wires seem to be in good shape. and the coil seems fine??

Where do I start looking from here?????

[86GT]

I've had a similar problem, and it occurs low in the rpm range, part throttle only. I'm thinking a fuel pressure problem myself. Whats your pressure at? How's your fuel filter, maybe it needs changing. Just some ideas to try and help you out.

Have you pulled codes from your computer? Maybe that'll give you some more insight. At least for me it lead me to the fuel pressure thing, since I'm running lean according to my o2 sensors.

[geno5.0]

I do not know how to pull the codes! I dont a have the Equip. I have My Fp set at 40. And yes it only happens at part throttle low in the Rpms, this is not a bad miss just ever so sligh? I also just replaced my fuel filter a month ago. I have been doing alot of work on my car over the last month.

I went racing about 3 weeks ago and filled up with 100 octane at the track! The next day I was working on my car and I disconected the Bat IE: reseting the computer. It relearned with the 100 in there and now I am using 92 that couldnt be the problem Could IT?

[Hozer 88GTConv]

Do yourself a favor and swap your distributor. Just remember your rotor position. I troubleshot a miss for months. It was a bad PIP sensor in my pos $200 Mallory distributor.
Good luck.

[USMC302]

Geno,

First, a miss in the low RPM range is commonly due to the #5 and #6 wires touching or crossing, make sure they are seperated well, or get some wire seperators and see if the problem still remains, also you could have fouled a plug out using the high octane but doubtfull, pull you plugs and see how they look, lean, rich or what, clean them or replace them, and double check the firing order.
Reseting your computer consists of disconnecting the battery and turning the light switch on for at least 10 min then reconnecting the battery. Just by disconnecting and reconnecting, I don't think you would have relearned the ECM. I will email you some good info I copied about octane, You most likely do not need to run over your current 92 rate.
Last, you will only need a cheap multimeter and a paper clip to pull codes. I will try to attach the diagram, if I can't I will email it as well. Good luck.

[bigred90gt]

As far as pulling the codes, there is a self test module inside the engine bay, all you need is a jumper wire about 5" long with 1/4" blade plugs on each end, and something to write with, if you have a check engine light. If so, start the engine and let it run until at normal operating temp. kill it and wait 10 seconds. In the engine bay, right next to the windshield wiper motor, there should be a harness with either 5 or 6 slots. 2 on top and 3 or 4 on the bottom. There should be a little jumper wire with a single slot in it just to the side of this. Plug the jumper you made into the top right slot on the harness and plug the other end into the jumper with one slot. Turn the key to the on position but do not start it. The check engine light sould look like it is shuttering rapidly, these are codes used by the dealer. After a brief pause the light will blink, pause for 1 or 2 sec and blink again. These are your KOEO, key on engine off, codes. For instance, if the light blinks 3 times and pauses then blinks 4 more times, this is the code 34. It should repeat any codes and all codes. If you receive a code 11, this means that no problems were detected. There should then be a 6-9 sec pause, a single flash, then a pause of another 6-9 sec and then another set of codes. These are your Continuous memory codes. Record all of your codes and then post them. Someone should be able to help you with them. There is also a KOER, key on engine running, test. You should correct any problems from the KOEO test prior to running the KOER test. corral.net has an indepth explaination and definitions for the codes. I think that depending on the year of your car, you may get 2 or 3 digit codes. I have a 90, and I received 2 digit codes. I hope this helps.

PS - If you do not have a check engine light, corral.net tells you how to do it with a volt ohm meter.

Anyone feel free to correct me if I left anything out.

[geno5.0]

Guys this is some good info I am going to look into this and get back with you !!

Also the reason that I ran 100 Octane is because I was shooting a 100 shot of N20. can never be to safe!

[geno5.0]

Ok here is what I got

flash short pause flash pause repeat same
than 6 to 9 second pause than the same


I took it as code 11---11 big pause 11---11
what do you think???

[gizmo83]

if im not mistaken... that would actually be code 22
2 flashes for the first digit, then a pause, 2 flashed for the second digit, then a big pause and starts all over right?

[geno5.0]

I thought so to but there is a 1to 2 second pause between

Flash 1to2seconds Flash repeat
Big pause 6-9 seconds
Flash 1to2seconds Flash repeat

[bigred90gt]

If I'm not mistaken, that would be code 11. Flash short pause flash then repeat. Long pause single flash long pause then same, flash short pause plash then repeat. It always repeats the codes. Per the instructions on corral.net, the code 11 would mean no problems.

[gizmo83]

yes that would be code 11, if there is a 1-2second pause between flashes..

[eatsgmcar]

I have the same problem... it seems that the engine is
missing in a regular way at low RPM. I can feel this when i pay
attention.

My car has high octance fuel (92), MSD 6 al and blaster
coil 3. Never found why the car is missing. However the
car goes really well on the race track.

SC

[Agent_4573]

There is a 2 second pause for seperation between numbers of the same code, there is a 4 second pause for seperation of different codes. Yours would be a code 11, everything is okay. But is this a KOEO or a KOER code? Recheck your codes with the engine running, then after you get the codes, press the gas slighty for a second or two, the ecm will run a cylinder check which checks compression, injectors, etc. on each cylinder. After you depress the gas and release, about 10 seconds later you will get either 2,3, or 4 flashes. 2 flashes means you ahve a 4 cyl engine, 3 means a 6 cyl, 4 means an 8 cyl. about 1 minute later you will get another set of flashes. 1 flash means cyl 1 is going bad, 2 means cyl 2 is going bad, etc. 9 flashes mean everything is ok. you might want to try this because it can tell you if you have a cylinder that is low on compression or possible a faulty injector.