• Welcome to The Truck Stop! We see you haven't REGISTERED yet.

    Your truck knowledge is missing!
    • Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
    • We have tons of knowledge here for your diesel truck!
    • Post your own topics and reply to existing threads to help others out!
    • NO ADS! The site is fully functional and ad free!
    CLICK HERE TO REGISTER!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

95 6.5 sputtering when reving

marvgarr

marvgarr

Active Member
Messages
126
Reaction score
40
Location
kingman az
I am having a problem with this engine. Some of you might know about my build on here (68 c10 6.5t). The problem I am having is it runs like crap if the ECT is plugged in. When the ECT is unplugged the computer says -35 deg and runs good at idle only. If you plug it back in the computer says the correct coolant temp but the engine hunts and blows white smoke. No matter if the ECT is plugged in or not when revved up the engine sputters and blows white smoke. The timing offset is -1.86 and base timing is around 3.5 when in timing learn. The injection pulse width was showing 1.95 which I believe is a default. The truck would not start today so I bought a new PMD and installed it. The truck runs now but is still doing the sputtering. The pulse width is now 2.12-2.14 before it would not move it now does. Now my injection pump is a 5521 and the computer I have no idea. I could not get the ECM with the motor so I bought an ECM from a 94 truck. This ECM has a BD diesel chip in it. Now could this be my problem the chip is not right for the IP? I was told it would work but I am now questioning the source. I see no other problems with the data out of the ECM when running.
 
In 94 there was an option for an HO pump with a specific ecm for HD 2500's and 3500's.

I bet you have that ecm with a generic IP
 
I should clarify, the chip is specific to the IP.

IIRC the 94 IP is a 5068, the non HO was a 5067 which is compatible with the 5521.
 
With your unique build, you may need to have a chip burned to reflect your rear end ratio as well as the IP and trans.

The chip should have a 4 letter code on it, someone on here (Ferm)? may know if it is for the HO IP or not.
 
Last edited:
Sounds like your temp sensor is bad. The gauge gets it reading from sensor in head. Ive had brand new sensors be bad right out of the box. Throw a meter on and see if ohms changes with temp.
 
Burning oil said:
Sounds like your temp sensor is bad. The gauge gets it reading from sensor in head. Ive had brand new sensors be bad right out of the box. Throw a meter on and see if ohms changes with temp.
Click to expand...
I was watching the temp out of the ECM not the gauge. I figured the ECT sensor was good since it goes to the correct water temp as I verified it with a thermometer.
 
NVW you might be right as I have no idea what pump was on the truck I got the ECM from. The chip just has BD Diesels part numbers on it. I did email BD Diesel and gave them the part number but they said they cant find any info about it. I do have the 4 letter code on the ECM case it self BJAX.
 
I was with Leroy on temp sensor, when you verified with a thermometer was that in comparison to the ecm, or the dash gauge? You have 2 temp sensors, 1 to the dash gauge and the other (the 2 wire) to the ecm.
 
As far as the ECT temperature it is reading right on the data out of the ECM. I think NVW is on the right track on the prom being wrong. I will check at work tomorrow and see what GM can get for a prom.
 
GM only has one chip for the 6.5 anymore it is BPAA. It is an automatic prom and I think it works with 5521 but I could not confirm that.
 
You must log in or register to reply here.
Back
Top