When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Here we go, normally on the 6.0 side, never had problem with 7.3 till lately.
Couple weeks ago truck started cranking slow, new batteries less than 6 months, 1 ended up bad, replaced...Couple cold mornings in the low teens, no start, plugged up for a bit, then fired... replaced GP and solenoid, no more problems till 2 days ago.... slow turn over with long cranks, then at normal ops temp cut off let and leave for 10-15 mins, may or may not start..... so searched and then hooked up the AE ran WOT test to look at the icp and ipr.
Started at 60mph to the floor, ICP 1900psi IPR 92% let off at 90mph ICP spiked to 3200
2nd test
60 mph ICP 1900, IPR 95% let off at 95mph ICP spiked 3400 psi
Thinking HPOP???? but honestly at a loss.
The 1900 psi readings was while running 90 & 95mph the spike came after I let off, not when mashed to the floor
Last edited by tjustice; 12-21-2014 at 07:13 PM.
Reason: More Info
Sorry forgot the details.....E99, with DPTuner set on 120..... factory injectors, with later model turbo with ebpv deleted. Normally ran on 80 street tune as daily driver, with sucky MPG like 10-11 running 3:73 gears....
Slow to turn over means long cranks before it starts or lower rpm's?
With you only hitting 1900 psi and the starting issues, I'd be looking for a leak on the HPO side. Any signs of oil in the fuel filter? Perhaps pop the valve covers and watch for an injector bubbling oil at the base while cranking or running.
Wow, 90% duty cycle numbers. Just a guess but try starting & running the truck with the ICP sensor unplugged. You'll get a check engine light but if there is a difference in starting and running it could be the sensor.
How many miles on those stock factory injectors? I don't like the ICP that low, some loss could be from injectors, but I also would want to see what ICP, RPM, voltage would be while cranking, rather than a weak HPOP. Especially having to plug it in to get started. These really aren't that much different than the 6.0's in systems and starting requirements.
I will get those numbers and post them up tomorrow.... Normally its not plugged up, just had to when had the glow plug issue. Injectors to the best that I know is 160k on them...Bought the truck used so, assuming are the factory ones.....
The injection pressure "issue" while accelerating is not related to the hard/no start. You need to realize that the particular calibration in question is likely commanding 5.5-6 milliseconds of pulse width (if you were actually able to maintain 2700-3000 PSI) and even more than that since you're not.
Run the test in "stock" and your numbers should be acceptable (2700+ PSI at <40%). If then AND ONLY THEN, you run into an issue with injection pressure, start looking for problems. But 1900 PSI when doing nothing more than running oil through the injectors really isn't that bad......
As for the starting problem, it could be a lot of things.
Load the stock tune and conduct your tests with AE again (add Fuel Injector Pulse Width with a max of 5ms to the PID list) - a perplexed look on your face is forthcoming. Then... load your tune, monitor with AE, and take the throttle to between 1/2 and 2/3 - but no more than that. At least one eyebrow will raise. Repeat the test with WOT. Whisky Tango Foxtrot is the standard reaction at this point. That spike you see is what I call a "Stinky Spike", because I first discovered it on my own on Stinky - the wonder truck.
You will be told you have a weak HPOP. This may or may not be the case, but a new HPOP will not be the complete cure. I have that tee shirt.
12-21-2014, 07:11 PM
