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Why do I still not have power????

I never said I couldn't afford the mods. I just can't afford a dmax or a gasser. That's why I'm working on it. I'm willing to bet my left nut that the timing is good. Next step is a 4" exhaust and then a tune. Thanks a ton for everyone's advise and knowledge.
 
If it wasn't set by somebody who understands this engine, I hope your right nut is up to doing the job by itself. IP timing with a DS4 needs to be set not only physically, but electronically (your PCM needs to recognize and properly modify the optic signals back through your PMD to control injection timing. There is about a million ways to get it wrong. If it was done at a GM dealer, you're probably ok. Anybody else likely doesn't have the correct scanner - they are many thousand dollars.

just sayin'. Not doubting you, but it's hard to diagnose over the net. We need solid information.
 
Nope, but if you don't have one, you REALLY need to be a 6.5 expert. Almost anyone can set timing close enough to run... With a 95, you put the IP within a range and set the computer to handle the signal. If the guy who set yours didn't have the equipment to handle the second part of that, then you need to get the computer (PCM-power train control module) to re-learn the IP position. Engine must be above 180*, etc.

VERY different process from any other truck.

Dealer can can check your timing- ask how much they want. My guy does it for $25, just for readings.

The reason I'm thinking timing is that it was changed during the engine swap. Nothing else will work right if the timing is off.
 
The reason I'm so sure is because the mechanic that fixed my wiring also changed the timing. I think he retarded it. Then I took it to the only mechanic I could find that knew the 6.5 and he said the timing was off and he fixed it.
 
Did the "rattle" change any when the timing was reset? More rattle means more timing advance. The computer 'sets' the timing, but, you have room to move the pump and be at a different part of the pump cam ring. The PCM needs to know where the IP is at to set the timing 'offset'.

How many miles since the new engine was dropped in and how many miles since the timing was done last? The timing chain stretches like crazy at first then settles down for a long sloppy life. Setting timing is a frequent tune up task. We also check the lift pump PSI every oil change to make sure it still works. The OPS, Oil Pressure Sender, burns out often stopping the lift pump.

You have the start of a nice setup that will get better MPG than stock and give you more 'useable' power. Absolutely the advice above for timing, a good tune, and exhaust will wake it up and change your mind. Don't forget to check the intake tract for a restrictive fender snorkel and plugged air filter.
 
I'll see about getting the timing checked. I think about 10k on the engine. I couldn't say for sure on the mileage or when the work was done. I am sure however that there's a fat stack of receipts somewhere. As for the lift pump, I wired that to a fuse that comes on when the key is turned. Got tired of that relay going out. And I have a k&n filter right off the turbo. (I know I should probably make a cai, but it's not at the top of the list)
 
Ask him what he set teh TDC offset at. The OBD1 will run without coding anywhere from 1.25 to -1.94 IIRC, but you need -1.25 to -1.94 for peak performance. -.75 gives an all around good quiet engine with decent performance, and is where most shoot for. Without having a TECH 1, TECH 2, or GMTD scantech, you cannot set OBD1 timing. NO aftermarket scanner is capable of entering time set and doing it. You can see the TDC offset, but not set it.
 
After seeing the burb burn out I must apologize to the OP. Even though it's a Duramax powering it...
Mods beyond my budget and tires are expensive yank me back to reality pretty quick.
 
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