Injector / ODB code check engine light.

[bralos]

OK got a new one for everyone, well old problem but still having it. From the time a bought this truck the check engine light would come on after driving 1/8 mile or so. Would go out after shutdown. Checked code and throwing a

DTC 97 Acb modifier Out Of Limits for Cyl 7

As some of you might remember I had a issue with PMD that you helped me through so this issue was put on hold. Now I have mounted the PMD and cooler in bumper and running again so changed out the injector on Cyl 7 this weekend. Still doing the same thing. Any idea where to check now? Lifters?

Problem: Explain your problem in concise language (ie: Cranks but won’t fire). ___Check engine light comes on 1/8 mile__

Demographics: tell us about your truck and your ambient conditions:

- Year: _1994__
- Truck model and class (ie: c2500) __C3500__
- Automatic or Standard __Auto__
- Mileage: (indicate miles or km) __189K__
- Replaced parts and mods (IP, PMD, chip/PCM, TM, injectors etc) _New PMD other issue, Fuel filter, Injector #7__
- Model: ‘S’ or ‘F’ engine, NA or Turbo, EGR? __S__
- Ambient outside temp: (indicate *C or *F) __10-55 always does it___
- What fuel are you using? (#1 Diesel, #2 Diesel, Bio, VO, WVO, etc) __#1__
- What fuel additives are you using? __Diesel Klean__
- Where are you located? __Smyrna Delaware__

General maintenance: inspect and evaluate the condition of each. When were they last changed?
- Air filter __3K__
- Fuel filter __<2 miles__
- CDR Valve? ___Dont know_
- Coolant – last flushed/replaced at __10 miles___
- Oil – synthetic/regular, changed at ___Needs it__
- Batteries – state of charge, (matched set) replaced at _Fine____
- Battery cables and grounds (removed, cleaned and tightened): ____Checked OK.__
- Glow Plugs - how many miles on them? ___unknown___ What type? ___unknown___
- Injectors - last changed at _______________


History: (Describe how the problem first appeared.)
- What were you doing when it happened? ___Always does it____
- How was the truck running fine before this problem appeared? ___doing it from the time i bought it.___
- Has this problem ever happened before? _______________________
- Describe any related factors that might be part of the problem. ______________
- Have you checked for DTC (Diagnostic Trouble Codes)? (Y.N) _Y__ And? DTC 97 Acb modifier Out Of Limits for Cyl 7
Diagnostics:

1] Starting:
1a] Does the engine start? _yes____
1b] Does the engine crank over? __ye___
1c] Are your batteries fully charged? __yess___
1d] Have you removed, cleaned, and tightened all battery connections? _yes____
1e] Does your Wait to Start light come on for a time? How long? _____
1f] Does your glow plug light come on? __yes__ For how long? __8-10 sec___
1g] Do you see smoke from the exhaust while cranking? What color? __nope__

2] Fuel Issues (if not running):
2a] Can you hear your lift pump working? ___yes___
2b] Do you get a steady flow of fuel from the water drain (T-handle) ? __yes
2c] Loosen the inlet line from the IP – is fuel coming out (Lift Pump on)? ____yes__
2d] Loosen an injector line and crank the engine - does fuel come out? ___yes_
2e] Do you hear a vacuum (hiss) when you remove the fuel cap? ___________

3] PMD / IP Issues
3a] Location of PMD (on pump, on intake, remote mounted) __Mounted on cooler, bumber - new item___
3b] Condition of Extension harness (if used) Vendor or Homemade? __vendor used___
3c] Condition of grounds / ground wires to IP / PMD. Check Harness. ___check, did this prior to PMD change____
3d] PMD Make: __stock ___
3e] PMD Age: ___couple years____

4] Stalling Issues
4a] Do you experience stalling only when hot? ___no____
4b] Does it stall under particular circumstances? (ie hit bump, or on accel) __no_
4c] Does pouring cool water over the IP seem to help with restarting? __no_____
4d] Is stalling momentary (engine recovers)? __does not____
4e] Does SES light come on when engine hiccups? _________
4f] Does cruise control quit working when engine hiccups? ___________
4g] Does re-starting seem to reset engine, restoring cruise and power? _________
4h] Changes to dash lights or instruments during stalling events? ___________

5] Running Issues
5a] On cold start, does upper rad hose get hard before engine warms up? _______
5b] Any bubbles or oil film in coolant overflow tank? _______
5c] Any white slime on oil surfaces (dipstick, CDR, oil Fill cap)? __________
5d] Excessive white smoke from exhaust on cold start? _________
5e] Excessive black smoke from exhaust under hard acceleration? __________

6] Performance Issues
6a] Do you have gauges? ___________
6b] Maximum boost under load? ____________
6c] Have you added a performance PCM (reflash) or Chip? _____no_
6d] Have you changed exhaust / downpipe / crossover? ____no________
6e] Wastegate – mechanical or vacuum? ______not sure_____

7] Temperature-related Issues:
7a] Single or dual thermostats? ____single_____
7b] Have you replaced them lately? Manufacturer of replacements? _yes 5 miles____
7c] Have you pulled and cleaned Radiator and coolers lately? ____nope_____
7d] Have you replaced the fan clutch? Manufacturer of replacement? ________
7e] (winter) Have you tested your antifreeze? Good to what temp? __________
7f] (winter) Are you using a winter grille cover? ___________

 

[NVW]

do you have a miss or is the engine smooth, DTC 97 is a cyl. imbalance as you know. You've changed the injector, do you have access to a comp. tester?

 

[bralos]

Engine seems to be OK. by that this is my first chevy diesel and not sure how smooth they are. I have a Ford 6.0 and like comping grapes to apples on that one.

But yes seems to idle ok. power band seems OK but by far not a lot of power.

Diesel compression tester, hum, do I hear a good excuse to buy one? LOL

Jonathan

 

[Matt Bachand]

Engine seems to be OK. by that this is my first chevy diesel and not sure how smooth they are. I have a Ford 6.0 and like comping grapes to apples on that one.

But yes seems to idle ok. power band seems OK but by far not a lot of power.

Diesel compression tester, hum, do I hear a good excuse to buy one? LOL

Jonathan

Harbor freight sells one for 25 bux that will work with 6.5's with a 4" 1/8npt Male/male nipple and female/female coupler.

 

[buddy]

Was there a washer when you installed the injector? Do you get much blow-by? When warm check the oil fill tube while idling and see if you get a lot of vapor rushing out, some is OK if it just rises.

 

[bralos]

There was a washer on the old injector. I used that one on the new one to just move the truck 30 feet. Waiting for the new washer to change out and run again.

Blow by you thinking rings?

One my way to harbor freight to but comprestion tester. Hum now on a gas engine I unhock power to distributer when I crank it. For diesel What is the best way to test the compression without starting truck.

 

[packratt]

Harbour freight has a kit about $35 that has the fittings that won't need an adaptor made up, also should work on your Ford.

You pull all the glow plugs, disconnect the juice from the IP and crank.

 

[bralos]

Yes stoped by HF on way home and bought kit. Wont be able to do compression test until this weekend. on the 6.5 where do I pull the glow plugs? Thanks

 

[buddy]

Do you get much blow-by? perhaps the imbalance would be caused by a worn ring or scratched cylinder wall losing compression.

Probably good to pull that cylinders glo-plug anyway to make sure its not broken inside of it

 

[Matt Bachand]

Yes stoped by HF on way home and bought kit. Wont be able to do compression test until this weekend. on the 6.5 where do I pull the glow plugs? Thanks

Pull the glowplugs out of the head THey are underneath the injectors, and should have a green wire going to each one, (may look black, but upon cleaning will turn green again) on my 97 anyhow.

It is very important to unplug your PMD or other measures to insure that your vehicle does not start when testing compression.

Some remove all 8 glows, and then test each cylinder, without glows in there would be no compression across the engine, but if your just testing one cylinder be careful. Not sure if that compression tester can take the explosion or not.

Someone else chime in here please, as I am not a pro at this.