Fasterer

Have you checked for any service codes. You can do it your self with a paper clip and it might just point you in the right direction.

masterprice33

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?

CentralCoaster

I've had ignition modules that tested fine, but failed when warm on the car. 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.

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.

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.

85vet

Had similar issue with car - module cured it!!!

rick lambert

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.

masterprice33

what about the times that the car stalls without the fuel pressure dropping down? what would that lead you to believe?

86Pacecar

The fuel pressure thing is a little wierd. However you stated that your mechanic is stupid and maybe he just wasn't remembering things correctly or the guage was bad. From what you describe it could be a number of things but if it doesn't happen till it's warm the HEI module is a likely culprit. NAPA will have the tester and part and will test it for free or at least should test it for free. It isn't a difficult repair and you could probably do it yourself but if your "stupid" mechanic does it make sure when he puts the new one in he uses the proper heat transfer grease(should come with the new module) so you don't cook your new one right away. The part will cost a bit more at NAPA than Autozone but I've found my local NAPA electrical parts to be the best. Without seeing your car we are just giving you some educated guesses but the guys here have given you some solid advice. Good luck and keep us posted as to the results.

masterprice33

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?

adown

I agree with coil or spark module inside the distributor overheating.

86Pacecar

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.

RRT vette

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.

masterprice33

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....

86Pacecar

With that explaination of the fuel pressure it definately sounds like the module is getting hot and failing. It's a very likely culprit and you can do this rather easily.

masterprice33

thanks guys I'm really hoping that the module will cure the problem.

LD85

Thegood part is that you can change thisout in less than 20 - minutes.

masterprice33

that's good to know, i'll remember that if my mechanic ever says, umm yeah that took about a couple hours

silver84

as a test, hot wire the fuel pump 'on',
see if anything changes.

MR.KIDD

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 )