I posted this in the TPI forum as well but I thought I might try you guys since maybe it's something I can scan and troubleshoot...


Ok, this has been happening off and on, very spontanious and not consistent. Like last night for example (please bear with me)...I've was driving around a bit, some highway and some city driving and we went to park and chat. Then after about 10-15 minutes, I hop back in my car and go to start it up, and it cranks and it cranks. Dammit! I try it again and same thing, it cranks and cranks and finally starts to catch, sputters a bit and then stalls. It did this two times and then finally started up but was running like crap till it ran for a bit. We drove a short distance, parked again for a chat and the same thing happened.

A couple things I noticed:

- the starter cranks ok and is only a few months old
- the engine when it finally did catch on seemed to be running rich for a short while (strong smell of fuel)
- I can hear the fuel pump running
- it was a little damp last night, I don't think that can affect a TPI motor, but I just thought I would mention it

Any help or hints you guys can give me would be great. I do have Craig Moates software and the ALDL cable to scan the car if anyone knows what I should be looking for. Thanks in advance for anyone that can help.



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1987 Camaro IROC-Z
350 TPI (L98), HyperTech Airfoil, K&N Filters and modified airboxes, AC Delco RapidFires, Taylor SpiroPro 8mm wires, Energy Suspension polyurethane bushings for front and rear LCAs and sway bars, KYB struts and shocks, BFG g-Force Z-rated tires, MAC STB, MAC SFCs, JET low temp stat, CarSound Hi-flow Cat, 3" Mandrel-bent pipes, Flowmaster muffler, Corvette Servo, TransGo Shift Kit, Corvette 2000 Stall, TruCool LPD tranny cooler, T-tops.

2001 Sunfire GT
2.4L, 5-speed, K&N cone filter, interior detailing, 200W Monsoon Sound System (8 speakers), Silver Metallic exterior with grey interior.

Web: http://www.angelfire.com/on3/whitelightening

 

Nobody



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1987 Camaro IROC-Z
350 TPI (L98), HyperTech Airfoil, K&N Filters and modified airboxes, AC Delco RapidFires, Taylor SpiroPro 8mm wires, Energy Suspension polyurethane bushings for front and rear LCAs and sway bars, KYB struts and shocks, BFG g-Force Z-rated tires, MAC STB, MAC SFCs, JET low temp stat, CarSound Hi-flow Cat, 3" Mandrel-bent pipes, Flowmaster muffler, Corvette Servo, TransGo Shift Kit, Corvette 2000 Stall, TruCool LPD tranny cooler, T-tops.

2001 Sunfire GT
2.4L, 5-speed, K&N cone filter, interior detailing, 200W Monsoon Sound System (8 speakers), Silver Metallic exterior with grey interior.

Web: http://www.angelfire.com/on3/whitelightening

 

I'd say you should check the resistance of your injectors when cold and when hot; there shouldn't be a difference or any more than an ohm. Sounds like they're getting heat-soaked and not firing (or firing properly), causing your starting problem. Another possible problem is that one or more of your injectors (or your cold-start injector) might be leaking, causing it to get flooded. Next time you have this problem, try starting the engine with the gas pedal floored (shuts off injectors during start-up).

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Greg Westphal
'87 IROC 355TPI/A4

 

I had a similar problem and still haven't figured it out. Next time it happens, try having the throttle FLOORED or wide open while cranking, suprisingly it will catch.. I don't know what causes that either but that seems to get my beast started. If you figure anything out let me know.



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1987 IROC-Z L98,SR,EB 6085's,LPE 219/219 Cam, Crane 1.6RR, EB TPI Base, 58mm TB, Stock T5, 30lb SVO, AFPR, K&N, EB TES, Catco Cat, 3" Borla Cat-Back, Accel cap,rotor,distro/other crap, Aluminum DS, 94 Disk Rear, Adjustable Prop Valve, Precision 3.73 Gears, Weld in Sub-Frame Connectors, Hotchkis LCA's, KYB Shocks/Struts, Poly Bushings all over the place, Moog Upper/Lower Ball joints and Tie Rods ends/Idler Arm, Big stereo, 730SD Conversion.

To see the ROC, Check out the webpage Here

 

Flooring your throttle and holding it before cranking is "clear flood" mode and basically, your injectors are off as long as you're holding the throttle to the floor.

 

Thanks guys, I will try the pedal trick and checking the resistance on the injectors. I'm also gonna try to get some readings on the CTS as well.



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1987 Camaro IROC-Z
350 TPI (L98), HyperTech Airfoil, K&N Filters and modified airboxes, AC Delco RapidFires, Taylor SpiroPro 8mm wires, Energy Suspension polyurethane bushings for front and rear LCAs and sway bars, KYB struts and shocks, BFG g-Force Z-rated tires, MAC STB, MAC SFCs, JET low temp stat, CarSound Hi-flow Cat, 3" Mandrel-bent pipes, Flowmaster muffler, Corvette Servo, TransGo Shift Kit, Corvette 2000 Stall, TruCool LPD tranny cooler, T-tops.

2001 Sunfire GT
2.4L, 5-speed, K&N cone filter, interior detailing, 200W Monsoon Sound System (8 speakers), Silver Metallic exterior with grey interior.

Web: http://www.angelfire.com/on3/whitelightening

 

afgun, where did you find that information out? I think that is some very good info. That would explain alot. I need to adjust my injector pulse width when the engine is warmer then.

Thanks,
Brendan

 

I believe that I read it in the Helm's. Additionally, you might check to see if you have leaky fuel injectors. Check your fuel pressure after you shut it off and it sits for a little while; if your FP drops, then there's a diagnostic procedure to see if it's the fuel pump, pressure regulator, or leaky injectors.

 

I know this is not your problem, but I want to give you an example of what happened to me in my 90 Riv. When the car would get hot, & I tried to restart it, it would only crank, no fire.

What it was was the crank sensor (I know f-bodies do not have crank sensors). Once the car cooled off a little it would work fine. You might even want to look into your distributor. Problems like this are really difficult because they are intermittant, and when the car is cool enough to work on, everything works fine.

Also check your cold start injector. that would make life miserable if not working properly. Thats why I am using an 89 chip.

I have no idea what this has to do with DIY & programming, but oh well.

Good luck

John

 

Just a thought guys, but what do you think about it having to do with the IAC? Do you think if the IAC was adjusted too high it might cause problems? I'm thinking of resetting it because it does idle a little high sometimes (like around 850 or so).



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1987 Camaro IROC-Z
350 TPI (L98), HyperTech Airfoil, K&N Filters and modified airboxes, AC Delco RapidFires, Taylor SpiroPro 8mm wires, Energy Suspension polyurethane bushings for front and rear LCAs and sway bars, KYB struts and shocks, BFG g-Force Z-rated tires, MAC STB, MAC SFCs, JET low temp stat, CarSound Hi-flow Cat, 3" Mandrel-bent pipes, Flowmaster muffler, Corvette Servo, TransGo Shift Kit, Corvette 2000 Stall, TruCool LPD tranny cooler, T-tops.

2001 Sunfire GT
2.4L, 5-speed, K&N cone filter, interior detailing, 200W Monsoon Sound System (8 speakers), Silver Metallic exterior with grey interior.

Web: http://www.angelfire.com/on3/whitelightening