Mystery Fault 98 corvette
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Mystery Fault 98 corvette
Day 4, no start. Car ran fine the night before it didn't. I have the reduced engine power, service abs/traction control. Engine cranks but has no ignition. I found a solenoid stud was broken on the starter, replaced with new starter. I've disconnected the STARR plug for the seat. I have pulled the chassis grounds for those systems and cleaned/tightened. Battery was measuring fine but still, replaced with brand new one. I used Bill Curlee's guide to repair the ignition and checked the Theft Deterrent Relay.
When I try to clear the DIC codes they immediately repopulate. The P0601 is the only code that HP Tuners pulled that the DIC didn't show.
I'm absolutely out of thoughts and forums to weave through. I've turned to Facebook corvette groups as well with nothing working. Could it be the PCM? I can still read/write to it with HP Tuners.
Any ideas?
When I try to clear the DIC codes they immediately repopulate. The P0601 is the only code that HP Tuners pulled that the DIC didn't show.
I'm absolutely out of thoughts and forums to weave through. I've turned to Facebook corvette groups as well with nothing working. Could it be the PCM? I can still read/write to it with HP Tuners.
Any ideas?
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P0601 is the PCM “kiss of death” !!...so you are not just getting spark ??...what about injector pulse ??...do you know how to check that with a 12 volt test light ??....check PCM fuse 16...see if it’s blown....if not you can connect a voltmeter lead to the top of the fuse...either test points will do...connect the other lead of the voltmeter to battery positive...we are checking for the “voltage drop” between the battery and the fuse...shouldn’t be more than maybe .1 or .2 volts. Try swapping the ignition relay 42 with another..,try that too !!...does the Tach move at all during cranking ??...if not it may be a crank sensor.,,if you are lacking ignition you won’t see the Tach move !!...does the fuel pump prime for 2 seconds with key on ??
ps...with a 1601 I’d check all PCM power and grounds before calling a bad PCM !!
ps...with a 1601 I’d check all PCM power and grounds before calling a bad PCM !!
Last edited by C5 Diag; Jul 15, 2019 at 11:31 PM.
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In my experience with HP tuners killing a PCM, I want to say the code was a 4 XX but I cannot be sure. It has been some years.
So while I can't help you with that, I can tell you that the PCM part number for the C5 is the same as was used on the F body's. You will need one of a particular era and I don't think it will be a 98. My C5 was a 98, I think I had to go to a 99 but don't quote me on that. Bottom line is, for a lot less money than the Corvette Parts people will sell you a C5 PCM, you can get an F body PCM for next to nothing. Just make sure it's the same part number and you're good to go. I know because in my 98, btdt.
So while I can't help you with that, I can tell you that the PCM part number for the C5 is the same as was used on the F body's. You will need one of a particular era and I don't think it will be a 98. My C5 was a 98, I think I had to go to a 99 but don't quote me on that. Bottom line is, for a lot less money than the Corvette Parts people will sell you a C5 PCM, you can get an F body PCM for next to nothing. Just make sure it's the same part number and you're good to go. I know because in my 98, btdt.
Last edited by K-Spaz; Jul 15, 2019 at 11:26 PM.
