AJ-Question - Page 3

submariner409 · #31 (**permalink**) 02-21-08, 11:11 AM

OK..........08/98 puts your car in the very first batch of the '99 model run assemblies, which moves the CKP idea to a back burner. Late 05/99 began the first '00 engine assemblies.

Back to the drawing board.

rhw1 · #32 (**permalink**) 02-21-08, 11:35 AM

Quote:

Originally Posted by submariner409

Would fuel trim swings set a P code?

rhw1.........did you pull the MAF when you did the IAC cleaning? Is there ANY chance you hit or moved one of the tiny wire resistors on the MAF voltage bridges? Should be 3 resistors with steel leads electro-welded to the signal and ground bridge network. They're tiny and fragile. Just another maybe.....

Click on the below pic and scroll in. These may not be your exact MAF, but they show (look carefully) the 3 resistors across the larger support wires. The little black thermistor at 1 o'clock is the IAT sensor. The pic also shows that a JET MAF is nothing more that a mechanically modified OEM DELPHI unit.

Answer to Submariner:
I did take the MAF sensor when I did the cleaning, but I was careful as I had read advice in the forum. Also dealer did the following at 68K miles and 40k miles: "Intake and fuel service including cleaning air intake system, fuel induction system and installing BG44K injector and intake system cleaner." I am sure my stalling problem started well before the 68K cleaning was done as I had hoped the 68K cleaning would solve the problem. When this problem started, it was very infrequent; over time the frequency has increased so I have lived with it for a long time. However, I'm pretty sure it does not go back as far as the 40K cleaning. This is probably more information than you wanted, but I wanted to give you as much as I could as I appreciate your input on this.

rhw1 · #33 (**permalink**) 02-21-08, 11:38 AM

Quote:

Originally Posted by eldorado1

When it is warm, do you notice a hesitation if you slightly apply the gas?

Answer to Eldorado1:
There is no hesitation on slight application of gas or any other time. Other than stalling problem, engine runs great. Thanks for your help.

eldorado1 · #34 (**permalink**) 02-21-08, 11:59 AM

I would clean the EGR valve. If it 's sticking and leaking, it could be enough to mess with the idle. So be sure to check the pintle to see if it has any resistance or is jammed open.

I would not rule out a sensor malfunction, but without a scan tool it will be difficult to find, so this is a good (cheap) place to start.

rhw1 · #35 (**permalink**) 02-21-08, 07:24 PM

Quote:

Originally Posted by eldorado1

I would clean the EGR valve. If it 's sticking and leaking, it could be enough to mess with the idle. So be sure to check the pintle to see if it has any resistance or is jammed open.

I would not rule out a sensor malfunction, but without a scan tool it will be difficult to find, so this is a good (cheap) place to start.

I'll pull the EGR valve this weekend; thanks for the input.

eldorado1 · #36 (**permalink**) 02-21-08, 11:44 PM

Can someone with an OBDII manual post the sequence to pull the MAF/MAP/TPS readings on the dash?

AJxtcman · #37 (**permalink**) 02-22-08, 08:34 AM

I was thinking about the same thing.

I am not sure how, but I will look for the procedure to do this.

I would look at the fuel trim or O2 readings through the DIC. The fuel trim reading will be the best way. Try short term if you have two people.

Bring up the Values on the DIC.
Spray Carb Cleaner around the Backfire Valve. The values should swing 10 to 20% quickly.
After that Spray the intake manifold and head area. The intake gaskets go bad. On decel the vacuum leak gets bigger.

If you can't pull this up on the DIC you could spray the cleaner, but the PCM is so fast I don't think you will see a change in the RPM or they way it runs. If you do get a change in RPM or it runs rough for a second you have a leak.

rhw1 · #38 (**permalink**) 02-22-08, 12:19 PM

Can someone tell me where the backfire valve is? Thanks

AJxtcman · #39 (**permalink**) 02-22-08, 01:11 PM

Quote:

Originally Posted by rhw1

Can someone tell me where the backfire valve is? Thanks

This one is sealed shut.

AJxtcman · #40 (**permalink**) 02-25-08, 01:33 PM

I got the car back today, so I could spend more time with it. I am pulling the intake off. The only DTC set this time was the P1599.

I did not even check the fuel trim this time. Just off with the intake.

Last time in I sprayed the gasket area and the fuel trim jumped

AJxtcman · #41 (**permalink**) 02-25-08, 02:37 PM

The intake gasket was worse off than I thought. I will post pictures soon

rhw1 · #42 (**permalink**) 04-05-08, 08:42 PM

Quote:

Originally Posted by eldorado1

I would clean the EGR valve. If it 's sticking and leaking, it could be enough to mess with the idle. So be sure to check the pintle to see if it has any resistance or is jammed open.

I would not rule out a sensor malfunction, but without a scan tool it will be difficult to find, so this is a good (cheap) place to start.

Problem seems to be solved; it's been over a month with no stall/near stall(was happening at least weekly). Thanks to all for help; prize goes to Eldorado1. I cleaned EGR valve at his suggestion; this solved the problem. One curious note to me; when I pulled EGR valve, it seemed to stick in the shut position? I cleaned/polished seating surface(not pintle) with steel wool. Eldorado1, you're the man.