Truck Quick Specs

97 350 E40D, Rosewood DIY 160s,BD2 Turbo,Western Plow GPR,TS6POS,EBPV Gut/Del,99 Intercooler,FPR Mod,etc

Well i have been fighting with this truck for awhile now on cold starts. even mildly cold it doesn't like to start. it eventually will but it takes forever.

If the truck is plugged in I don't seem to have any issues. Even in the summer when it was warm if the truck was cold overnight the first start of the day it always stuttered a bit.

Here is the AE Logs, these were from complete cold start at about 40F truck has been sitting for about 4 days at temps between 30-50F.

Truck DID NOT start after these crank attempts(but would have if i would have kept going) and after being plugged in for 20 or so minutes i cranked about 3 times and it seemed endless, didn't even try to start then out of the blue just fires perfect, no stumble or anything. This has me thinking its a sticky IPR, almost like once everything warms up enough the IPR unsticks and it fires.

https://docs.google.com/spreadsheets...it?usp=sharing

https://docs.google.com/spreadsheets...it?usp=sharing

 

Why does it show nothing for the first 5 seconds then bam rpm and ICP both come up? If it was cranking I would look at cps not providing a signal.

 

Pretty sure that's just where o had key on but not cranking?

 

All conditions are there to start except "Injector Pulse Width".

1. RPM, minimum 100 rpm cranking speed (When warm it should be over 180 rpm).

2. ICP, minimum required for starting 500 psi if no rpm signal, ICP won't go over 400 psi.

3. Voltage during cranking 7-10 volts minimum depending on year.

4. Pulse Width; 0 ms means no sync, 1994-1997 .42 ms indicates that PCM and IDM are in sync (on 99-03 it should be .60 ms) and the PCM is waiting on the ICP to reach the minimum pressure. When min. ICP is reached PW should change to 1-6 ms.

Without the change in pulse width to at least 1 ms the injectors won't fire. I would suspect a bad CPS. Although it is detecting RPM it might not be detecting cylinder 1 and 4 properly as those slots in the cam ring gear are different sizes.

 

Thanks! This looks promising ibwill have to try and track down a CPS.

One question. Is there a reason it would start better when plugged in? Just a warmer CPS? Or do I still maybe have another underlying issue also?

Thanks
Dustin

 

My first question would be have you checked to see if all 8 glow plugs are good?

 

Just tested 3 of 4 banks. Only got a reading on 2 of the 6 pins tested one was .08 one was .09 my leads had a resistance of 0.2 themselves. I didnt bother testing the back drivers plug as it appears I need glow plugs regardless.

 

Things change when engine is warmer, parts expand .. etc.

I agree, could be multiple issues. However even with dead GP circuit pulse width should still go up and fire injectors.

That should help on cold starts. On CPS make sure you get one from Ford or International. The part store items are very poor quality and usually introduce problems like you are currently experiencing.

 

I am going to pickup a CPS Tomorrow from Ford/International whoever has one in stock or can get it quickest.

Also priced all all my glow plugs and VCG and harnesses, i did them on my last truck. these gaskets and GPs were done about 5 years ago according to PO and they look really good and clean but for the $110 i might as well replace them with the Dorman ones.

Should i be worried about injector o rings? i notice IPR duty gets to 45%

 

Be VERY careful of the Dorman parts. That have been known to cause more problems than they fix

 

I have heard that from some, i did the Dorman VCG on my last truck and really liked them. i actually liked them more than the Ford because the harnesses are all one piece so there is no chance of a clip or anything breaking underneath.

but maybe if my FOMOCO ones i good i can save the $110.

 

Don't think so as IPR duty cycle keeps going up due to injector pulse width not increasing, for whatever reasoning Ford engineers decided on. As far as glow plugs and VCG and harnesses you might want to check the actual glow plug resistance(s) if all harnesses look good, your call.

 

At least with the FOMOCO ones if a harness goes bad you can replace just that ONE harness and not the whole assem

 

Is there a way to test just the VCG and Harnesses if the GPs are bad? i tested GPs and def have some bad but not sure if the gaskets are good. I imagine i would have running issues if the VCG were bad. Truck runs fine

 

Ohm out each piece separately