Suddenly super lean while at cruise - Page 2

93sc · 11-21-2005

Quote:

Originally Posted by scheides

Good question. Voltage is rock solid during the condition ~14.1v.

I don't know then. Friend of mine had a problem when his alt was on teh way out that he would get a voltage drop and that would cause him to go way lean.

**scheides** · 11-21-2005

Quote:

Originally Posted by EclipseGST

Have you messed with the TPS at all?

yes, it seems to be operating correctly.

**scheides** · 11-30-2005

Last night I swapped in a new ignitor/power transistor. I drove around a bit in first and second gear to test it out, and the issue was still there. Damn!

I park the car, defeated again. This morning, I head out to go to work, and plug in a datalogger. Cleared the slew of CEL's I have (my egr stuff is removed, and now i see that something is goofy with my ISC) and head out. On the way to work I just take it easy, to avoid 'the issue' but it doesn't show up. I drive over to MAS in St. Paul over lunch, no issue. I drive around after work and tonight trying to get it to come back, and voila, no lean-out!

If it doesn't come back in 2 weeks (like it did last time), looks like I owe EclipseGST and blageo some reward money!

**scheides** · 12-14-2005

Well well well, look who's back. I had a great time with my car over the last week. It's never been more reliable and fun. Started at the first crank, drove around at pretty much any rpm I well pleased, boosted, cruised, etc etc etc with no problems. I was talking with my cousin up north, and he asked about my car and how it'd been. I filled him in, and since it was now running smoothly, he asked for a ride. So, I decided to drive it up to Fergus Falls (my home town) for the weekend. The drive there was perfect, I sped (conservatively) the whole way. As I pulled into town, it had started to snow and so I was going a bit slower putsing through town. About halfway through town, I felt a shudder...THE SHUDDER...I drove a bit further, and my suspisions were confirmed, the issue was back. 500 miles after the it had gone away, the problem was back! GAHHHH!!!! I'm pissed and feel like strangling someone...but who's to blame?

Anyways, I swapped the plugs and checked out a few connections as best I could (no garage) to no avail. Tonight, I swapped out the power transister with another BRAND NEW one, and ran some nice ground wires to various grounding points. NO LUCK. I moved my coilpack and strung it (temporarily) from the a/c line on the firewall. NO LUCK.

Does anyone have any further ideas for me? Here's my plans for shit to replace next:
-all the ground straps I can see. I'm not sure this will really help, but wtf.
-fuel filter
-ecu
-o2 sensor
-coolant temp sensor
-knock sensor
-I'm also going to try and set the base timing, does anyone have a timing light I can borrow?

EclipseGST · 12-15-2005

Snow/Water + Maft = Shudder! I recently had this happen in my car, about 1/2 a week ago. Found my Maft was covered in snow. Pulled it apart and it got wet inside, dried it out, put some RTV around the cover and wires and put it back together and it runs just fine. Make sure all your wire connections are good.

What are your settings on your MAFT? Also what are your settings on your AFC?

You dont have it on RPM mode or a 3.5" maf instead of a 3" maf or vice versa?

**scheides** · 12-15-2005

Right now the MAFT is zero'd out and it's run fine in the past. Airflow looks constant as this happens, so I don't think it's the MAF or MAF-T. I already have RTV around the maft cover, but I'll check that anyways. RPM mode...I think I have the white rpm lead hooked up, but I don't think it's in RPM mode.

Thanks for the tip!

-c

**scheides** · 12-15-2005

Ok, I held a blow-drier to the maf-t box (uncovered) for about ten minutes to no avail. it looked dry in there, but I did not take the circut board out from the box to inspect it. i'll do this later tonight.

EclipseGST · 12-16-2005

I'd make sure its not in RPM mode and its set to the correct size maf you have.

Is your fuel pump rewired? If so, what size relay did you use and did you try replacing that yet? I had a problem with the O-ring sealing on the pump and the car would run perfect with the LICP disconnected but as soon as I hooked it back up it wouldnt run for shit. I know this isnt your problem but it could play a small part in it. Atleast the relay could.

Just trying to suggest anything that could affect the way its running at this point.

**scheides** · 12-17-2005

Thanks for all the suggestions. I think I am on to something. After I blow-dried out the MAF-T yesterday, I went for a short drive, only a few blocks and the issue was still present. This morning, I started my car, and hooked up my pocketlogger. Since the 6-bolt I have in my car has all the EGR stuff removed, I have a CEL all the time. I realize this is stupid, but it's been this way since I bought the car. Anyways, I hook up the pocketlogger, clear all the CEL codes, and head off to work. As the day wears on, the issue is gone/not present.

Is it possible that if I have enough CEL's the ECU is going in into some sort of limp mode? Otherwise drying out the MAF-T is at the top of my hit-list for now.

EclipseGST · 12-17-2005

I think your getting a random misfire. Common issue in 2g's with 6 bolt motors. I'd just start saving for DSMlink because thats the only way your really going to get rid of it. By the computer getting a CEL it starts looking for other problems. You could do the Baro Wire mod but I dont trust that at all. I think VFAQ has info on how.

Try this. Next time you are at cruise and it starts to do this, flip the key off and back on quick and see if it goes away. As if you are turning the car off then back on. If it goes away, then you are definatly getting a random misfire. I use to have to do this on long trips, 3+ hours of driving at a steady speed it would start to shudder. I just flipped the key off and back on and I was good for quite a while. My money is on that!