I just put my 89 IROC back together and now have a no start condition. I changed out the heads, everything went smoothly. Upon reassembly I could not get it to start, even though it was fine a week earlier. It will sputter at idle and that is about it.
Upon hooking up my scanner I find I have absolutely no reading from my TPS. Checked TPS and I have 5V to it, I can ground it to the battery or either of the other two wires and come up with the 5V. Swapped TPS out with a known good one I have, no change.
So what could I have disturbed that would cause my TPS to suddenly not read to the ECM?
Thanks
Roy

 

I have never had a problem with a low TPS setting causing a no start condition. Did you move the TPS to try and get a reading? The only other advice I have is that it sounds more like a timing issue to me. Did you install the distributor in the same position in which it came out? Plug wires are installed correctly?
I know you can un-plug the MAF & IAC and start the car, can you do the same with the TPS? Maybe you got a loose connection in the pigtail of the TPS. Maybe un-pluging it will allow it to start?
Not much help.....I know...... -Nick.

 

Nick, I dont have a low reading, I have no reading from my scanner. Big 000 regardless of position. All of the other functions seem to read normally however. Matter of fact the TPS reads normally if you check it directly with a voltmeter. But for some reason it just isnt getting the signal to where it needs to go.
Roy

 

Well scratch the TPS issue but the wierdness continues. Today suddenly I have a reading on the scanner that the TPS is working normally. But I still have a no start condition.
After turning it over and listening to it sputter at idle, I realize it is rythmic and decide to do a hand test on the exhaust headers. What I discover is that I only have heat in #7, all of the rest are stone cold. So I check 2 other cylinders for compression, spark, and injector pulse. All of these things are there. I disconnect my digi MSD thinking it may have failed on me but the condition still persists even after it is taken out of the loop. So what I have is one cylinder trying to run, and 7 dead even though they seem to all have compression, spark, and fuel. Any suggestions?
Thanks
Roy

 

I would assume its something to do with timing. Have you tried finding top dead center on #1 and adjusting the distributor as needed. Your getting spark and fuel, but maybe not at the right time? Don't have the injector harness hooked up wrong? What are the plugs gapped at? Firing order is correct?
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Thats all I can think of......HTH......Nick.

 

That was the first place I went when it wouldnt start. It appears to be dead on. Everytime I have set the distributor wrong in the past I have had strange cranking and backfiring, etc. I have none of that, just one cylinder running, and 7 not.
Roy