Stall out, Oil Pressure Drop... *UPDATE* *AGAIN!*

[C.O.Jones]

Ok,
This one is really pissing me off… I’ve been watching the issue for about a week now and have narrowed it down.

Situation:
When the engine warms up (after running at ~190 degrees, or after running for about 20 minutes) the idling RPM’s drop.
If the car comes to a stop and is left to idle, the oil pressure drops to around 45, RPM’s drop to about ~900, and "alternator" <- scratch that, battery can drop to 11.
The car will continue in this manner for about 20 seconds before it dies (no sputtering).
After the engine has cooled for a few minutes the car will start up again and throw an SES light (unfortunately Autozone in my area doesn’t read codes and PEP Boys want $70 to read it).
Usually after a few starts the code disappears.

Here’s what’s been done:
The exhaust was replaced 2 ½” to 3” Cat back system. (7/03)
Changed out the O2 sensor after the Cat (looked like OEM) (8/24/03)
IAT relocated to airbox (4/03)
Manual fan switch (7/03)
Recently relocated from WA to Southern California.

I’m starting to think that it might be the MAF. If I hold up the RPM’s to over 1000 then the pressure stays up around 60.
The car wouldn’t start on me once in Washington about a month ago (shortly after the new exhaust), but since I couldn’t duplicate it, I dismissed it to not turning the starter key all the way.

I can only check the boards once or twice a day at work (still waiting for home phone line to be hooked up) so I’ll answer as much as possible when possible.

Thanks (PS. Sorry to anyone northbound on the 15 last Wednesday as it was me that stalled out in the fast lane around the 10)

[ August 25, 2003: Message edited by: C.O.Jones ]

[ September 11, 2003: Message edited by: C.O.Jones ]

[ September 12, 2003: Message edited by: C.O.Jones ]</p>

[speedy-v6-camaro]

First...the gauge on the dash is the battery gauge...not the alternator gauge...and 11 is really low. The alternator might be bad or the battery or both.

[98Camaro3.8]

Find somewhere to get that code scanned. That may tell you exactly what the problem is.

[C.O.Jones]

Already had the battery and alternator checked (sorry) - both were fine.

Will get the code read, but really pissed about having to fork out $70 for something so easy. Hell an oil change takes more resources, and is 1/3 the price.

[RAR]

If your car is OBD II, you can by the same scaner Autozone would use at Autozone for about $100 it is an Actron - it has 3 red 7-digit display and I think will just read codes.

That would be better then 70 to read it once...

Or you could be like me and sucker your friend to buy one, then you have one when ever you want [img]smile.gif[/img]

Try to get the codes (because it is throwing one) before throwing "it might be this" at the car - you could end up spending a lot of money...

[C.O.Jones]

Ok,

The two error codes I got were as follows:
P1651
P1652

One of these is a fan 1 voltage error (from the manual fan switch). The other was another chasis error.

Having read the earlier post RIP K.I.T.T. I changed the oil to a 10W40 Pen. I had the oil changed about 1000 miles ago at a Jiffy Lube...

Any other suggestions/ideas?

[C.O.Jones]

Ideas?

[Wicked 3800 V6]

You might have tapped the wrong wire when you setup your manual fan switch. Are you sure that you can turn them low / high / off? If you somehow tapped a bad wire in the engine bay, you might be sending an odd sensor signal.
-Rob

[C.O.Jones]

Rob,

I've double checked the connection over the past week, I even pulled out the console and filed down the solder connections at the switch (was afraid I was jumping connections).

I replaced the PCV valve this morning (old one sounded good). I went thorugh the idle process out of the Chilton book (with AC off turn on car and leave in P for 10 minutes, turn on AC leave for 10 minutes, put in D for 10 minutes, etc...). I turned on the fans at high and low, heck I even ran the engine up around 1200 RPM for a few minutes to heat up the engine. The oil pressure stayed pegged at 60. So I took it out for a drive.
Accellerated to 45 quickly and drove about 4 blocks. When I hit a light and stopped the pressure dropped to ~40 and the engine shook pre-stall... I limped it back to the garage.

Who sells the O2 sensor resistors? I'm starting to think that it might be the 3" cat.

No codes thrown.

[camaro_speedemon]

<blockquote>quote:</font><hr>Originally posted by C.O.Jones:
Ok,

The two error codes I got were as follows:
P1651
P1652

One of these is a fan 1 voltage error (from the manual fan switch). The other was another chasis error.

Having read the earlier post RIP K.I.T.T. I changed the oil to a 10W40 Pen. I had the oil changed about 1000 miles ago at a Jiffy Lube...

Any other suggestions/ideas?<hr></blockquote>

Both of these are due to the manual fan switch...the other one is listed wrong in the post you saw.

And you would've throw a code if the computer thought you had a bad cat.

[ September 07, 2003: Message edited by: camaro_speedemon ]</p>

[C.O.Jones]

I took it to the dealership Tuesday morning .

Tuesday Evening: Still hadn't done a diagnostic check.

Wednesday Evening: Did a diagnostic check can't find anything. Want to know if they can take it out to drive a bit. Sure, no problem.

Thursday Morning: Car runs fine, can't find anything wrong, pick it up. I ask to come by and take a mechanic for a drive to show them.

Thursday Evening: I go to the dealership to break my car. Warm it up by putting in D and running the engine around 1300 RPM's for around 7 minutes.
Take the mechanic out. Drive 3 miles, car won't stall out. Get back to the dealership, mechanic looks very doubtful. In parking lot, come to a stop and put in D for about 1 minute.... nothing breaks. Mechanic reaches for door and I take my foot off the gas.... BOOM car stalls and dies. Firsh thing I hear is "Don't touch anything" and the mechanic reaches over and tries to start the car.... nothing. Next thing I know he bolts off to the shop and gets a fuel pressure gauge. By the time he gets back the car has had sufficient time to cool, so of course it starts on the first try.

Now: Still at dealership, but I won. Dealer now get's to scratch their heads.

[Wolfy]

i had kinda a problem like that, anyways the way they finally caught it, was i took my mech out with his really nice scan tool, and it finally did it when the car was hooked up to the tool, while trying to start it, and drive it, so that is how i found it out, you might mention that to him, it should shed some light for ya

[C.O.Jones]

I got a call back from the Dealership.

There's a gasket leak on the manifold which is leaking fluid onto the camshaft sensor causing it to short out intermittently. ($850)

Oh, and my oil pan gasket and rear seal are leaking. ($700)

[img]graemlins/thumbsup.gif[/img] [img]graemlins/thumbsup.gif[/img] [img]graemlins/rofl.gif[/img] [img]graemlins/thumbsup.gif[/img] [img]graemlins/thumbsup.gif[/img]

woo hoo

[fenderman]

<blockquote>quote:</font><hr>Originally posted by speedy-v6-camaro:
First...the gauge on the dash is the battery gauge...not the alternator gauge...and 11 is really low. The alternator might be bad or the battery or both.<hr></blockquote>

Well, this gauge isn't exclusively the battery gauge either. It measures how many volts are running through the entire electrical system which is battery, alternator and all accessories. A proper level is 13.5 volts with the car running. This 13.5 volts is a direct result of the alternator. If you were to turn the engine off and put the key back into the run position, you would notice that the voltage reads lower than normal. This is because the only thing supplying power to the electrical system is the battery.

EDIT: The reason for the drop in voltage could have been due to the drop in RPM. Without the alternator spinning at its optimal RPM, it does not charge as well.

[ September 12, 2003: Message edited by: fenderman ]</p>