• 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!

Hummer p0216

ron993

New Member
Messages
16
Reaction score
20
Location
Tomball, Texas
I am new here and usually hang out on the Hummer forum. I just did a complete rebuild of the cooling system on my H1 and am now getting a P0216 code with the first start of the day. I can clear the code and it will not come back until the truck has completely cooled off. Below is what I have replaced:

Leroy's timing gears
fluid dampener harmonic balancer
leroys crank pulley
new alternator
new vacuum pump
new water pump
new power steering pump
leroys bypass restrictor fitting
new ron davis radiator and tri-cooler
new crankshaft position sensor

The truck has 68,500 miles on it, and has a new PMD and I have already swapped in the old PMD that i was running beforeIMG_20140403_081630339.jpg
 
Welcome to the forum Ron, nice looking Hummer.

Looking up the code, it appears You will need to get to a scan tool capable of checking the timing of the injector pump.
With all the work performed on the enjun, the pump timing is probably off.
 
Hummers all have exactly same engine and trans, ffm, etc as gmt400 6.5 trucks. Only 95 or older is n/a with db2. 96 & newer is gm6 or 7 turbo but instead of side mount turbo it is in center rear. Same ops, Lp problems, pmd issues, etc.

Yeah, he pm’d me on hummer forum- I sent him here cuz it is so many years since I had to wrench on ds4 that I forgot most of what I knew. Hoping someone else would hit the stuff I missed. Like @MrMarty51 good call- that makes sense. Of coarse timing after timing chain coming out.

I told him the basic like doing the optic vs cps sensor test by unplugging 1 to test the other in case new cps is bad. He uses Power Kleen fuel additive. I said maybe store current fuel in jerry cans and get new fuel and add 2 stroke to make sure stepper motor isn’t “dry”.

By his list of new goodies, you all can tell Leroy is a vendor there also. ChevyClause spreading toys...
 
I will check the sensors tonight.

What additive should i be using in the fuel? There is diesel kleen in the front tank, but just diesel in the rear tank. I am checking to see if anybody near by has the computer programs that were recommended. Leroy is on the other side of town so that may be an option.
 
I will check the sensors tonight.

What additive should i be using in the fuel? There is diesel kleen in the front tank, but just diesel in the rear tank. I am checking to see if anybody near by has the computer programs that were recommended. Leroy is on the other side of town so that may be an option.

Well worth the drive to see him in person! @Burning oil
 
Ok I unplugged the crankshaft sensor and started the truck. It started eventually but ran rough. I plugged it back in and unplugged the optic sensor(I think) it was right in the middle of the pump and had a white lock pin on the clip. The truck would crank and just eventually barely start and die immediately.

Does this mean the crankshaft sensor is bad? I bought it from AutoZone
 
Did you pull the crank sensor out? I unbolted mine tthe other day and it hits the steering box before its free. I only gave it 30sec before putting it back in to get on with my starter project. Does the steering box actually need to move to get it out?
 
PO216 is timing control circuit which deals with the stepper motor on the injection pump. I'd be using a scan tool to watch desired vs actual timing. My initial thought is that it's not able to achieve the correct timing advance on cold start so it tosses the code. It could also be that the pump needs re-timed so the stepper motor can achieve the proper swing of advance.
 
Back
Top