Running Intermittently, ECU Problem

[RMiller]

So sometimes my car doesn't start. Rarely. And it has died twice while driving it. To make it start again, I have to take out the EPROM chip, somtimes just put it back in, and sometimes put in another and it starts right up. Then I can replace the original and it will still start. The car has only died with one chip, it has never died with the other (the one I replace the other with to start it).

Is there any way a chip can work only part of the time? Also, my timing is not set to 14 btdc which it should be at according to JC Performance where I bought the chip. I think my timing is more like 12 or 13, which sucks pretty bad; my question is can the timing effect the chip's effectiveness to start? When it dies and doesn't start, there is no spark. Suggestions?

[RMiller]

dum dum dum dum dum

Timing is now at ~14 btdc. Was at about 5 btdc. Oops, that's what I get for eyeballing. Also, the CAS bolts left clear marks of where it used to be for some time (I assumed it was at 15 btdc), but it either it was all jacked up or my $30 timing light is all jacked up. Funny thing, there was no change in performance as far as I could tell. But it idled a little different, that's all.

Talk to me if you have some insight.

[float_6969]

First of all, do you have the detenation sensor hooked up? Secondly, what did you hook up the timing light to in order to shoot the timing? If you reply with "the loop at the back of the ignition coil harness" you're timing is wrong and you need to do it again. That looop is purely an RPM signal.

[RMiller]

I used the wire coming right off the coil pack on cylinder 1. I hard wired the detonation sensor to the ecu, and I don't get a check engine light. I thought det. sensor also. The timing light might be off, I don't know. I might try to time it to a happy medium and see if it feels better.

[RMiller]

Well I had a pretty bad vibration and tapping sound coming from my engine, and I think it was because I had a motor mount upside-down. So I fixed that and the vibration isn't so bad. Maybe the knock sensor detected that and retarded timing? Now the car feels a lot faster. I get about .1 bar at 2500, .2 at 3000, and .4 at about 3800. At full throttle, it feels about as fast as my 2000 mustang gt, so I'm guessing it's in the 14 second 1/4 range. Then again, I'm shifting really slow so I don't slip the clutch much because it's new. Pretty fun to drive. Also my temp is very consistent. At idle and standing still temp stays at 78*C. It hasn't gone above 90*, which happened at heavey load up a hill. More boost will be fun.

[float_6969]

That could be a possibility. But if it's running well, then enjoy it!