My mystery no start issue is back!

**HOBS** · 08-21-2011, 07:59 PM

So my T/A is having fits again. I drive and start it hundreds of times without issues but sometimes it just won't start after I turn it off. It'll crank and crank but won't fire. The only lights on the dash are the air bag light, the check gauges light and the security light(all solid not flashing). I can hear the fuel pump running and I've tested the pressure half a dozen times and its always in spec. The last time it started doing it I figured out that when I swapped positions of the Ignition and Starter relays than it fires right up and usually doesn't have issues for another 100 or so starts. When it does do it again I swap the relays again and it works perfectly again. It seems to be getting worse though because yesterday it wouldn't start after I drove it around town. So I swapped the relays it fired right up and ran fine up until I pulled into traffic at which point it just flat ass died(not amusing). I swapped the relays one more time and it drove fine again. I'm almost 100% sure there's something wrong with the ignition system but I don't know what and it confuses me that its not consistent. Anyone got ideas cause my electronic diagnosis skills are severely lacking. Let the ideas flow guys!

**Cutlass** · 08-22-2011, 05:26 PM

Sounds like you might have a connection issue at the ignition relay that you temporarily fix by swapping the relay. To confirm this, try wiggling the IGN relay with the engine running. If the engine dies, then you're half way to a diagnosis.

**HOBS** · 08-23-2011, 04:56 PM

Tried wiggling it and the motor wouldn't even sputter. Would it be possible for the relay to be bad even if it tests out o.k.? Any other ideas on things to test?

**Cutlass** · 08-24-2011, 04:02 PM

I don't think its the relay. Any green corrosion on the IGN relay terminals?

**cammed goat** · 08-24-2011, 05:05 PM

It sounds like it is heat and vibration related to me.

**Knight** · 08-24-2011, 05:53 PM

Swapping relays would normally rule out a bad relay. It sounds like a bad connection to me, or possibly even a short. Electrical problems that don't show up all the time are always the hardest to trace out. I would break out a meter the next time it happens and start tracing voltages to see where it's stopping at. It may be something ignition related even, before it reaches the relay.

**HOBS** · 08-25-2011, 11:54 AM

There's no corrosion on any of the terminals. I would be inclined to think that its heat/vibration related except sometimes I've driven it somewhere and after its sat for an hour it starts fine. I drive it half a mile down the road turn it off and it won't start.

**HOBS** · 08-25-2011, 12:02 PM

Originally Posted by Knight

Swapping relays would normally rule out a bad relay. It sounds like a bad connection to me, or possibly even a short. Electrical problems that don't show up all the time are always the hardest to trace out. I would break out a meter the next time it happens and start tracing voltages to see where it's stopping at. It may be something ignition related even, before it reaches the relay.

God I hope its not a short somewhere, I hate tracing those! As far as breaking out the volt meter that in itself is complicated because its so random and it always seems to do it when I'm nowhere near my tools.

**cammed goat** · 08-25-2011, 04:09 PM

When the car dies, and you try to re-fire it, do you see any smoke or smell anything burning? I ask as my previous car had the same symptoms you described. Turned out the starter wires shorted themselves together and shut the ignition system down when warm. Let the car cool down and the car fired right up. If the car shut down, and I attempted to start it, I had smoke and a burning electrical smell.

**JayTA98** · 08-26-2011, 09:44 AM

have you looked at the wires that go to the terminal from the back of the box? you could have corrosion and you wont see it from the top.

**HOBS** · 08-27-2011, 08:45 AM

I don't smell anything burning or see any smoke so I don't think its melting anything and least not yet. Did your car still crank after it died? I'll have to pull the fuse block on my next day off and see if its corroding at the base. Unfortunately it hasn't done it the last few days so diagnosing has gotten complicated.