Hi,

Calling out to FTE´s for some assistance. Currently on the road and experiencing some problems that I cant put my finger on, which started on a 5% grade doing 60, on 75hp tune with a TS chip, in 4th gear between 1.5 to 2k rpm (¨lugging it¨). Had been running previously with no tune and with no problems. Its when I maintain this scenario that the problem re occurrs.

2 issues happened when problem started, 1st was a compressor surge which was easily ¨fixed¨ by letting the foot off the throttle. Will deal with this later with a better compressor wheel. 2nd issue has me a bit dumbfounded, and its what I best can describe as a defueling problem, which progressively worsens over run time. The engine seems to lose power over a 5 to 10 minute period and begins to stutter, not to the point of shutting off but yes to the point of having to maintain 2k at 40mph on a very small grade. If it shifts to 4th and rpms lower it gets worse. If I stop the car, engine off for a minute and then re start it seems to disappear for a minute.

I had been dragging a P1249 code which made be think it was defueling. I changed the map sensor and tested and for 2 hours the truck ran great, after which it began again. Unplugged map sensor, ran great for 30 minutes and began again.

I am running PID´s with forscan on adroid and have a regular boost between 18 to 22 (jumps to 30 on grades dowshifting with CC but last run I stopped using the CC on grades), ICP and IPR measures are standard. Torque slip is near to 0 when running at highway speeds. EOT and TFT are well and cool. Sadly I do not have a gauge to measure EGT´s. Maybe this is a over heating issue? Given the sound of stuttering I thought maybe an injector problem? These were recently remanned at a local shop with new seals and put too spec (re used old nozzles).

Only codes I have are pre existent and therefore I suppose non related (B1203, B1352 and C1145). I did of course get a P0237 from disconnecting the MAP.

Im running as said a TS chip. Modified stock turbo with a WW assembly, deleted EBPV, larger exhaust housing on turbo. Adrenaline HPOP, stock remaned injectors.

Where should I start looking? This problem is re occurring and im 1k miles from home. Currently at a stop on the road having lunch, hope to get some quick answers.
Thanks!

 

Are you near a town where you could find some fuel hose pressure gauge and a hose barb, so you can monitor fuel pressure while you drive? Have the in tank modifications been done? Have you checked the fuel bowl and filter? Are the fuel heater and water sensors unplugged? How about your oil fairly fresh and full? Is unplugging the ICP worth a try?

 

Oil has aprox. 3.5k miles on it. 15-40w rotella synthetic. I hace to admit I did put a couple if quarts of regular mineral diesel oil in there a few months back when in need so there is a mix.

im thinking possible oil aeration. I am carrying only 4 lts, will drain a few quarts and replace with new. When home will give a fresh filling.

I did hear an enhanced ticking sound coming from the passenger side injectors when the problem was occurring. Hope its this and not a failing injector. Will buzz test when possible.

 

I would expect oil aeration would cause an ICP code of some kind. Low fuel pressure and air in fuel will cause injector knock and power loss as well. The air can be tough to track down but a fuel pressure rig is simple to throw together. Heck what's your air filter look like?

 

Drop the tank. Sounds like the screens in the mixing chamber are clogged. Search Hutch mod. Guzzle has a write up here https://www.guzzle7pt3.com/hutch.php

For a roadside fix, you could clean the screens and reinstall them. Delete them when you get home.

 

Hutch mod has been done in tank with new pickup and filter. All new filters throughout with no more than 3000 miles on them.

just finished 100 miles and it ran aweful. 4lts of replaced new oil did not help. Aereation is discarded.

Icp unplugged made no difference. Running average pressure’s of 1400 to 1500.

The fact that this happens upon engine having warmed up (after a few hours), and no codes, discards any fuel pressure related problem, unless at certain op temp more fuel is required.

it reaches regular op temp (90c) way before it starts to run like crap.

 

Im running a 6637 Donaldson filter, I cleaned it 2000 miles ago and lubed it up with new air filter oil.

Will remove and see if idling gets smoother.

 

Just as clarification:

Did you put air filter oil on a paper filter? I'm not saying that's your problem but paper filters cannot be wet or oiled.

 

Point taken, filter was blown with compressed air and lightly oiled. Ive ran the truck for several thousand miles afterwards with no problem. If this was indeed a mistake, I dont think this is currently causing the issue at hand 🤔

After each engine shut off and on, even if a minute at so, the truck recovers power for a brief moment.

 

Can I manually gauge fuel pressure by measuring the time it takes to fill the fuel bowl?

 

Performed buzz test and it checked out ok. Injectors all sounded fine.

 

Not pressure, not even flow really that would change with pressure. Are you not near any kind of town with an auto parts store? All you need to monitor fuel pressure is 5-6 feet(2M) of 5/16(8mm) fuel hose, 100 psi gauge, a hose barb to fit the gauge to the hose, and 2 clamps. Take the line off the drain on fuel bowl. Install one end of your hose to the drain with a clamp. The other end gets the gauge. String the hose out of the engine compartment and hang it from your driver's mirror. Open the drain valve and start the engine.

 

Thanks, not much supply in rural Chile.

As soon as I see a decent parts store i´ll stop and try to source these supplies and get back.

This does seem to be a fueling issue, i´ll take a look at all filters on the truck tomorrow am. There is a leak in the new fuel bowl as well, on the drain valve, i´ll inspect more closely and try to see if there is a leak source I am not aware of.

 

Does Chilean fuel have a rep for cleanliness? Honest question. The symptoms sound like clogged OEM in tank screens, if they are still in there.

That said the way it runs well for a moment after cycling off and on smacks of a sensor giving the PCM bad info after the PCM starts looking for it.

 

I'm probably too late to this party but if the issue only occurs when the engine is warm, it may be the magnet on the IPR starting to fail. If you can find some in rural Chile, get some computer duster and spray at the magnet with the can upside down to cool it. See if that resolves the issue temporarily. The magnet will need replacing.