Thread: Occasionally Sputtering then back to normal? Help

I've now had this happen twice and want to see what everyone thinks. I went for gas the other day in the GTP and after filling up, I started the car and it immediately died. I started it again and it sputtered and didn't want to run. I gave it a couple revs and everything went back to normal. I pretty much dismissed it at the time because I've had cars not quite start on the first attempt and then hard start on the second try. However, on the way home, it sputtered a little at a stop sign but picked right back up and had been fine.

We drove it around all day today with no issues what so ever. Then, tonight Mystie drove it up town to pick up a pizza and she came in and told me as soon as she pulled back into the driveway, the rpms dropped really low to the point the lights all dimmed, then back up to normal, then back down and it died. I went out and started it and it spit and sputtered and kinda felt and sounded like a miss. It didn't want to stay running and I had to keep my foot on the gas. I gave it a couple revs and it went back to normal again. I shut it off and restarted it and it was fine. Later, I took it for a short drive up town and back home and it didn't act unusual at all.

Any ideas? I find it odd that it only is doing it randomly but goes right back to normal if I rev it a little. When I say rev, I don't mean to redline, just a few quick taps on the gas.

No check engine light has been tripped and I checked all my electrical connections, battery, fusebox, plug wires, vacuum lines, etc. I'm at a loss. Any help would be appreciated.

Jay

Originally Posted by FoSHO99

Is it similar to when you unplug the maf sensor and try and run it, or could you unplug the maf sensor now and see if it runs the same way?

Anyway you can get a scan posted up when it does it/low idle? Could it be the rear 02 sensor sim.? Mine went out and will cause the rpms at low idle sometimes they will rock the rpms back and forth from very low rpms to about 1200 rpms, back and forth...

I'll try unplugging the MAF tomorrow. Rear O2 sensor is non-existant and it is turned off in the PCM, been that way for a few years.

Nice, thanks. I have a cat now, so I really just need to turn it back on. Actually it is just set now to not report, not sure if that makes a difference. Anyway, the car was catless for many years and was set this way with no issue. Still kinda makes me wonder if this is the root cause since it just started this all of the sudden.

Well, yesterday I cleaned the MAF and IAC. The MAF wires were black and shined right back up with some MAF cleaner. The IAC was the same, all black and I got it all shiny and clean again along with the hole in the TB it fits into. Put in a new fuel filter and my old one I could barely blow through so it definitely needed that. Also reinstalled a working rear O2 sensor and I am having all that turned back on in the PCM tomorrow hopefully. My idle really smoothed out with just those things I did. Not that it I thought it idled badly before, but it was noticably smoother I thought. My wife drove it today and did not have any problems with it like I had described in the original post. But, like I mentioned, it hasn't done it everyday so time will have to tell.

A buddy of mine was over and had a little pocket code reader and we plugged it in just to see if anything popped up and it pulled a P1133. It never tripped the check engine light though. We cleared it and it didn't reoccur. A member on our local board says he gets that code from time to time since he installed headers so maybe that's why it was there since I recently installed SLP's.

I dunno, I'll update if anything goes haywire again. I appreciate the help.

Originally Posted by FoSHO99

When I installed headers it took a while before it started acting up. Im just going throught the problem right now and the next step for me is to flash a 2000 gtp .bin on my car and see how it goes. I have the p1133 code pop up at times and there is no check engine light, i also have the bank 2 cat codes that pop up and no check engine light. Sometimes the cel will come on, but its not consistant. I always had a rear 02 sim. installed. My car wouldn't die, but im not heavily modded. Maybe scan to see what your ltft are doing and if your gas mileage has been suffering, because mine has.

Scanning is on the agenda for tomorrow. The local member I mentioned said he went with the Denso front O2 sensor and his stopped tripping the P1133, so you might give that try.

Originally Posted by Abrasive

Scanning is on the agenda for tomorrow. The local member I mentioned said he went with the Denso front O2 sensor and his stopped tripping the P1133, so you might give that try.

Brian also confirmed tonight that the Denso O2 stopped his P1133 code as well. Scanning today went great. I turned my rear O2 back on and everything leveled out and we got a really good tune in it. Runs like a champ and we were seeing zero KR. I'm happy, and have to say thanks again for that link to the 01+ O2 sensor thread. I rarely check the tuning section so that really helped out.