1985 CONFUSING STALLING problem
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Joined: Apr 2006
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sorry everyone i've been on vacation for a couple of days, just got back and have seen your replies. This is the first time someone has suggested the HEI module, we don't have an AutoZone here hopefully Kragen or Napa will do it for free. How do you check for codes with a paper clip? If you could just lay out the steps for me here that would be awesome. Thanks again guys, the mechanic I'm working with is stupid I'm beginning to think, I'm sending him lots of information and he's slackin big time, I have to see if he worked on the injector stuff over the weekend, grrrrrrrrrrr. Oh, with the HEI module, what would ALL the symptoms be for a failed module, just basically what I've described? Does that account for the random drops in fuel pressure also?
Team Owner
Joined: May 2002
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Originally Posted by 86Pacecar
I've had this problem before and the module would only fail once warmed up. Took it to my local NAPA and had it checked and it would fail rather quickly. Put a new one in and no more problems. Good luck with the repair, intermittants are a PITA.
There is really no way to test it aside from putting it in the oven right beforehand. By the time I would go through the diagnostic steps over again, it would cool down enough to work.
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to central coaster
do you have any suggestions for me on what to do? just real frustrated with this whole process, i don't want to fork all the dough over for one of the so called high quality shops to mess something up again.
Race Director
Joined: Feb 1999
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From: Indianapolis IN
Originally Posted by masterprice33
do you have any suggestions for me on what to do? just real frustrated with this whole process, i don't want to fork all the dough over for one of the so called high quality shops to mess something up again.
Go down to Autozone etc, buy an HEI module @ $40, take the distributor cap off, put the HEI module in and put the cap back on.
Melting Slicks
Joined: Oct 2000
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From: Heidelberg PA
Cruise-In V Veteran
Originally Posted by LD85
Go down to Autozone etc, buy an HEI module @ $40, take the distributor cap off, put the HEI module in and put the cap back on.
Had similar issue with car - module cured it!!!
Le Mans Master
Joined: Oct 2003
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From: seattle WA
One of the reasons they run the ignition module through at least ten cycles is so that it gets hot, less than ten, you just don't know.But it's still the FP drop that brings me back to injectors,fuel pump or regulator.
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Burning Brakes
Joined: Mar 2003
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From: NW MN
Originally Posted by masterprice33
what about the times that the car stalls without the fuel pressure dropping down? what would that lead you to believe?
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well about the FP readings I personally witnessed them happen that way, and the gauge is a brand new Hypertech. It doesn't seem to happen. It's kinda weird, but when the problem FIRST started I could start the car just fine when it was cold and it would run fine, and then randomly down the road somewhere it would stall out, then it would either start right back up or take longer to start up, but it would in fact start up. Later on, it would start up fine cold and then eventually when it would stall, it would become increasingly hard to start, and even got to the point where it would not start at all, it would crank and crank, and the crank would get weaker and weaker, until it would not crank at all. Now at this point, even when cold and sitting for a couple days it will take forever to get the car even started and when sitting in idle without even driving it it would stall out, and either the FP would stay around 40 psi or would drop rapidly. How likely could this problem be coming from a bad computer or a bad ground? How would I check for a bad ground?
Burning Brakes
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From: NW MN
Have you checked spark during the stalled out condition? My guess is still the module. The fuel pressure drop from how you describe it seems to happen after the car stalls which points to spark, however if it dropped rapidly causing the car to stall I would continue looking at the fuel system. At this point it is your chice to throw parts at it but the module is not that expensive.
Le Mans Master
Joined: Feb 2006
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From: Louisiana
I'm going with most on here and say the ignition module. As you say it only gives you most trouble when it's hot. I'm sure you mechanic has checked for spark. The fuel pressure is a little strange because it usually either drops or holds. The injectors need to be ohmed and a leak test done on. Your mechanic needs a process of elimination. I usually will start with fuel, then spark, then air/sensors ....that is if no codes. You will need the ignition module tested and most places will do it for free. I also wonder about the fuel pump/relay wiring.
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reply to 86Pacecar's suggestions
When the fuel pressure dropped rapidly, it happened AFTER the car stalled, and then at other times when it would stall the FP would hold at 40. So from what you are saying this points to a spark problem, meaning the ignition module? Again thanks everyone for the input it's helping me out a lot, just wish the mechanic would make the time to perform some of these tests!!! ahhh man I need to have a corvette guy in this town but there is none, unless any of you know a corvette guy in the Humboldt County area in northern California....
Racer
Joined: May 2004
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From: NORFOLK VA.
Do you know anyone that would loan you a ecm for test purposes I have seen several cases that one would cause the problems you are describing and not throw 1 code I even have had one go bad and lock the injectors open,with no code.Also I have had one have a bad fuel pump relay and a oil sending unit go flakey at the same time.
(From experiences I have had )
(From experiences I have had )