okay, it's not fixed

[jayro]

Hi all,
Had some drivability issues the other day. When I pulled the codes I found a TPS code (made since as idle was staying up even when I was off the throttle and I was having issues pulling codes cause it wasn't getting a signal when I stepped on the gas). I replaces the TPS and everything seemed good. Took it for a few 20 min drives and had no issues. T
Then today I went out and washed it ect and was cruising for about 30 min and it did it agian. Felt like it missed for a second then started to loose power. When I pushed in the clutch it died. It started back up and ran fine for about 1 minute then did it agai. I pulled the codes agian and this is what I got:
511 No power to pin 1 or bad PCM
542 Fuel pump open/bad ground, always on
412 and 411 idle speed not controlled to high and low
225 knock sensor not tested

Cyclinder balance test all good.

I also got code 129 the first time I ran the codes, but not the second.

This only seems to happen after it is warmed up in 90+ temps and after spirited driving.

Thoughts

Jeremy

 

[CademiaX]

Well, I would say something with the fuel pump being a bad ground would cause it to do that.

So possibly just a bad ground.

What grounds have you checked?

Might want to check the fuel pressure when it acts up again.

 

[jayro]

The fuel pump is a 155lph that was replaced 2 winters ago. It only has about 15k on it. Is there a specific ground I should check for the fuel pump? I have the fuel pump so I can get to it pretty easy. Could the pump be overheating if the gas level was low and temp were in the 90's? I thought that a 542 code was normal if the car died while driving.

Jeremy

 

[CademiaX]

might want to check out the CPS too. IF that was going bad you would have no spark and no fuel. Very common, when the car gets warmed up it will fail.

I personally would start with the CPS if that 542 is common when it dies for any reason. Also sounds like the fuel pump and grounds are fine then.

 

[boat]

From what Hunter said, it sounded like it may be your computer with the codes you were getting. Bubba is having a lot of the same drivability problems you are experiencing. Bubba was getting some of the same codes, but got also "998" code which more than likely "could" be the computer.

 

[oneqwicksho]

I just had the same problem today. I put in a new tps cause the old tested bad. No change still would die. Then got code 998 and 12. So I figured computer is dead because, I just put in an x2j two weeks ago and now problems. So, switched the old computer back in and, no change again. Well come to find out that my 1 week old fuel pump is ******** the bed. I guess. I put a full tank of gas in the car and no problems now no dieing no nothing. Tell me that don't sound weird?

 

[jayro]

Thanks for the ideas. I'm going to pull the pump and make sure all seems okay with it. I've only ever had any issues when temp was higher (90+). Would the heat play a factor with the pump or PCM? Is there a way to bench test the fuel pump? Would there be a way to test the computer, or is it one of those things that you don't have a way of knowing unless it completely fails? SOrry with all the questions, just not sure where to start.

The CPS should be good.....just did a full 60k about 15K ago. If it happens agian I may pull a plug to check for spark. The tac was working the entire time though.

Jeremy

 

[Huntervf]

511 and 542 don't worry about. 511 is set because of your LPM and 542 will get tripped if the car stalls, which it did.

129 suggests a MAF prob, even if it didn't pop up the second time. I believe you said you have a 75mm on there? Is it hooked to a stock airbox or another intake setup? May want to get some electronics cleaner and give the MAF sensor a good clean, as a dirty MAF can cause problems.

411 and 412 came up before, though I fail to see how an idle issue or ISC would cause the car to stumble while under power.

I'd pull codes 2 or 3 times over the course of a couple hours, just to make sure the computer is running the diagnostic okay. If it does, you can probably rule out a PCM problem.

I recall something from many years ago about a fuel pump problem (or fuel pressure regulator) being related to heat, but I can't remember the details.

 

[jayro]

I went ahead and cleaned the MAF. It is hooked up to the stock airbox, but I usually clean it fairly regularly since I am running a K&N. I went ahead and pulled the Fuel pump to take a look at it. When I put the new pump in I noticed that it hung down slightly lower than the old pump. when instaling it into the tank the screen filter at the bottom would contact the bottom of the tank. I was thinking that if this was being pushed down it could cause the pump to have to work harder to pump the gas.....therefor when the gas was low (not enought to cover the pump) and it was hot outside it might cause the pump to overheat. Does this sound like a possibility, or am I just grasping at straws?

Jeremy

 

[hawkeye18]

I think straws. Past that, I can't really offer any more than everybody else has said...

 

[jayro]

I checked the fuel pressure. IT was right about 34-36 at idle. When i would rev the engine it would jump a little to about 38, then drop to about 30-32. It stayed at 32-34 with constant throttle or gradual increase in throttle. It primed (KOEO) fine. IT is a 155lph. IS this a little on the low side? I did a search and came up with pressure up to the low 40's while on the gas.
Also, the brass tube coming out of the top of my pump doesn't fit 100% flush to the tube it is connected to (the one with the small canister on it). Mine has maybe a 1/4" gap from being flush.