WTF...Check Engine light!!!

[thelastgoodbrother]

Ok on my run to and from Mass. I experienced a check engine light after about two hours of driving. This is the scenerio:

I was slowly pushing on the gas when I could feel the car start to shudder/sputter. It last for a few seconds and the check engine starts to flash and then the car chimes...a few seconds later the car surges like it's fine and then goes back to sputtering. The whole thing lasted until I nailed it and powered out of the sputter. At first I thought that it was because the car had been sitting for about a week buried in snow. I ran through the rest of that gas on the trip up.

Before I headed back today I filled up with 93 because they didnt have 91 (I am running the Jetchip stage 2). Once again after a couple of hours on the highway it started to do it again. This time I didnt nail it I just cruised and let work it out on it's own. Once I got home I parked and left it for about 15 mins. When I start it up again it its running rough and the check engine light stays on. I start to drive it and it smooths out, but the light is still on. I get to my destination and leave it parked for about an hour...now the light is off and it's running fine.

Any ideas or similar experiences? This sucks cause my magnum lip and new wheels are due this week.

[fnkychkn]

a flashing MIL (malfunction indicator lamp) indicates a severe misfire. if you keep driving it like that, it could cause irreperable damage to the catalyst.

how to display trouble codes

[thelastgoodbrother]

What does that generally mean? The car has done a couple of times before, prior to the install of the Jetchip. I guess that I need to get to the shop asap. Should I pull the Jetchip prior to going?

[fnkychkn]

try removing the Jetchip, then pull fuse 11 in IPM for 15 seconds. reinstall fuse and road test. could be caused by the chip.

[thelastgoodbrother]

I just ran outside and did that code search...no codes showed up.

[fnkychkn]

since you have no EVIC, codes should display in odometer window.

[thelastgoodbrother]

That's what I mean it just showed the "-----" and then it went to done...but no actual codes showed up. I am hoping that is a good thing.

[fnkychkn]

not really. it would be easier to diagnose with a DTC to guide us.
like i said, flashing MIL = severe misfire. can you drive it to your dealer? they may be able to tell which cylinder is affected.

[pigpen]

Stupid question and answer!

Bad gas??

I had problem kinda of like what you had and it went away after I ran the car dry and filled backup with usual gas brand. My car was not happy at all barely ran, black exhuast smoke, rough ideal all because of bad gas.

[thelastgoodbrother]

The car is fine now. I can make it to the dealership...and with 34000 on the odometer, I would like to catch this while its still under warranty.

I thought of bad gas too, but I ran it until it was just about empty going up. Then I filled up while I was up there, making sure not to top off. Which is what somebody had told me the problem was before. That when you top off gas goes into some type ventilation resevoir causing the car to act the same way.

[fnkychkn]

glad to hear she's feeling better. a thorough check-up may reveal some answers. please keep us posted.

[Campy]

I had something similar and stopped at the dealer, it was a "multiple engine misfire" and the dealer updated some software. It's been fine since, although my 3.5 has a little stumble across 3500 rpms.

[Cdn_Magnum]

Should always go back to a known good... remove anything thats not normal... in this case the JetChip. Never assume that add-ons cant go bad
its not unheard of for electronics to go bad.

[MooNDoGGie]

I agree Russ. Especially since the Jet chip install almost always means removing the boot from the plug on the piggybacked PCM. This boot removal leaves the electronics open to the elements unless you take the time to shrink wrap it like i did.

[cadzilla74]

Fouled plug maybe? Or a plugged injector? Are you using any injector cleaner at oil changes? I'm using Gumout Injector cleaner and get a 2-pack at WalMart for $4...just toss it in with a fillup after each oil change. My 10/04 build Mag RT has taken every StarScan change and Superchips tune I have thrown at it from day one without ever throwing a code until this past winter when my thermostat got stuck open and failed...