[JDFRRC]

Hoping someone can point me in a direction to get me started. New distributor installed. Replaced amp module. Smooth idle but it takes 3 cranks to get her going. ‘94 with a 3.9. Any ideas? Thanks!

 

[JDFRRC]

FYI - it may be only at hot start. Waiting for it to cool down to check.

 

[JDFRRC]

Confirmed low or no spark at high temp. Starts right up when cold. So am I down to it being either another IAM or the fuel temp sensor?

what would keep cooking the IAM if that’s it?

 

[JDFRRC]

And another question - is it still possible to get a relo kit stateside? I can’t seem to find one in stock.

 

[IchWill]

I made the wiring harness, have to be careful on the routing. Mine would not start if the harness I made was anywhere near the backside of alternator. Of course...I should have used shielded wire. No issues with it for a few years now. Can't remember the State side company I ordered the connectors from...

 

[custard pie feet]

If you can not get one in the USA, then Powerspark in the UK sell one at a very good price.

 

[JDFRRC]

Thanks for the help. I’ll message powerspark.

Does everyone agree with narrowing this down to the IAM again? Is it possible to keep cooking these like this? Seems like they should last a few trips and not throw an immediate fit. What would cook these so quickly?

I’m also suspecting the fuel temp sensor here. I haven’t tested it yet though.

I really want to (pretend to) trust this truck. What else should I be checking to cure this?

 

[custard pie feet]

Amplifier module should be good for at least a 100 thousand miles, mine has. Have you checked your coil? Fuel temp would have nothing to do with poor spark. Have you set the distributor up properly?. Leads and rotor arm, simple things but can cause your issues.

 

[JDFRRC]

I will check the coil again. The distributor is newly rebuilt. Coil is new. Amp module new. Wires new. Plugs new.

 

[custard pie feet]

When you say rebuilt, what was done? Is it 3 pin or two on the amplifier? There are only 4 things that cause no spark, amplifier, coil, leads and plugs. Are the wires from the distributor in good condition? Is your battery good?

 

[custard pie feet]

You will need to get your multi meter out and check all connections from amplifier to coil.

 

[JDFRRC]

Fair enough. I’ll go through all the ignition checks again.

It never fails to start. It starts immediately and purrs when cold. It takes 3 or 4 cranks when the engine is warm.

 

[JDFRRC]

Been checking and diagnosing. Finally got a code 15 - fuel thermistor. Is that the fuel temp sensor? Is that what’s located in the fuel rail on the front passenger side? Thanks!

 

[OC95RRCLWB]

Something else to check is the air gap between the star wheel and pickup coil in the distributor. Set to .010" using a brass feeler gauge only.

 

[JDFRRC]

Ok. I’m not sure how to do that. Need to look it up and find some pictures.

 

[Bill B]

My 95 fuel temp sensor is on the drivers, left, side of the fuel rail by the TPS. Only thing on the right hand side is the Schraeder valve to test fuel pressure.

 

[JDFRRC]

My 95 fuel temp sensor is on the drivers, left, side of the fuel rail by the TPS. Only thing on the right hand side is the Schraeder valve to test fuel pressure.

are you able to snap a pic?

 

[Bill B]

Sorry am out of town. Try googling 95 RRC 3.9 v8 fuel temperature sensor images.

 

[Bill B]

Just found this picture. You are lucky.

 

[JDFRRC]

Thanks.