94 6.5 Sub SMOKESSSSSSSSSSS

[Robyn]

Hi all
I am well versed on the mechanical injection 6.2 and 6.5 engines and what they do.
I just bought a 94 6.5 sub and this thing runs ok but if you romp on it hard at all it throws out enough smoke to kill every mosquito for 5000 miles. I am suspect that maybe a sensor such as Map or something that controls the turbo waste gate. It will also smoke a lot if you romp on it sitting still in the driveway.
Thing runs good otherwise. Coughs up a load of smoke on startup too then cleans out. I am leaning towards one of the sensors that tell the IP what to go do with itself. ???????

[rjschoolcraft]

Check your wastegate system. Search on this topic and you'll find all kinds of information. The operation of the vacuum pump and wastegate solenoid must be verified.

[BrentN]

Welcome to the world of 6.5 TD
I definately agree with RonnieJoe. My Suburban had the same issue when I bought it. Usually one of the three: Vacuum Pump, Vacuum Solenoid or Vacuum Lines. You want to avoid doing any heavy motoring until you fix this. Black Smoke=High Temp. Not good for any diesel...especially not ours. There should be enough vacuum present @ idle to close your wastegate.. Definately do the search like RJ said...common problem, very common solutions.

[autocrosser]

If you eliminate the waste gate as a problem check the cat converter. It's pretty common for them to plug up. Disconnect it at the down pipe and drive it to see if that corrects your problem. If it's plugged you will also be able to see the soot covering the interior of it.

[Shuck]

Robyn,

Bnave95 and I are still troubleshooting our problems (same as yours) in this thread (http://forum.thedieselpage.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=1;t=008206). Mine is down to a bad PCM, but there are lots of other options before going there.

This troubleshooting list assumes you are having symptoms associated with no/low boost such as black smoke, lack of power, or no boost indicated on gauges (if installed) and that you have checked your air filter and intake path for obstructions.

1) Check wastegate actuator to see if it can be moved freely (by hand) at engine idle (and is in the retracted position).
-no movement, but not retracted: Suspect stuck wastegate or stuck wastegate actuator (rare).
-no movement and retracted: Suspect problem outside of wastegate system. Possible plugged cat, bad turbo, or post-turbo intake air leak.
-yes: Go to step 2

2) Check for 15" vac at wastegate actuator connection with engine idling.
-no: Go to step 3
-yes: Suspect bad wastegate actuator.

3) Check for 15" vac at rear port of wastegate solenoid with engine idling.
-no: Go to step 4
-yes: Suspect bad vac line to wastegate actuator from wastegate solenoid.

4) Check for 25" vac at line into front port of wastegate solenoid with engine idling.
-no: Go to step 5
-yes: Go to step 6

5) Check for 25" vac coming out of vac pump at front of engine with engine idling (use caution around fan and belt).
-no: Suspect bad vac pump
-yes: Suspect bad vac line to wastegate solenoid from vac pump.

6) Verify 12v between pink wire at wastegate solenoid connector and ground (but not yellow wire) with ignition on.
-no: Go to step 11
-yes: Go to step 7

7) Unhook connector and jump 12v across wastegate solenoid from battery to any known ground (note the + sign on the solenoid and be SURE to insulate the positive lead so the two don't touch). Then check for 15" vac at wastegate actuator with engine at idle.
-no: Suspect bad wastegate solenoid.
-yes: Go to step 8

8) Verify wire continuity between yellow wire at wastegate solenoid and pin A3 on the PCM (3 in from bottom right on middle PCM connector) with ignition off. Best to use an ohm meter to check resistance.
- < 5ohms: go to step 9
- > 5ohms: Suspect bad wiring connection between PCM and and wastegate solenoid. Most likely near the solenoid connection.

9) Verify yellow wire at wastegate solenoid is not shorted to ground. Use an ohm meter and measure resistance between yellow wire connection and any ground with the PCM disconnected and ignition off.
- < 100kohms: Suspect potential short to ground in wire.
- > 100kohms: Go to step 10

10) Unplug all PCM connectors and leave sit for a couple hours (to clear PCM). I've never actually heard of this working, but it was suggested to make sure a PCM reset didn't fix the problem. After a couple hours, plug PCM back in and check for 15" vac at wastegate actuator with engine idling.
-no: Suspect bad PCM
-yes and still have smoke while driving: Go to step 1.
-yes and no more smoke while driving: Congratulations, a PCM reset fixed it.

11) Check ENG-1 fuse in fuse box under hood. Use an ohm meter, sometimes bad fuses can look good.
- < 5ohms: Go to step 12
- > 5ohms: Replace Fuse. If black smoke continues, go to step 1.

12) Verify wiring between ENG-1 fuse socket and pink wire on wastegate solenoid connector. Use an ohm meter.
- < 5ohms: Go to step 13
- > 5ohms: Suspect bad wire connection between fuse block and wastegate solenoid connector.

13) Verify pink wire on wastegate solenoid connector not shorted to ground. Use ohm meter between connector and any ground.
- > 100kohms: Go to step 14
- < 100kohms: Suspect wire short to ground, replace wire or find short to ground and repair. If black smoke continues, Go to step 1.

14) Check for 12v between ENG-1 fuse socket and ground with ignition on.
- >= 11v: Perhaps we missed something to get to this step and have voltage at this connection. Repeat step 6.
- < 11v: Suspect wiring problem between ENG-1 fuse and 12v source, possible bad fuse box, possible bad wiring to fuse box. This is rare.


Hope this helps. If anyone has any steps that I missed in this troubleshooting guide, let me know and I'll edit it. Perhaps we should put it in a new post and make it a sticky called "Black smoke or low/no boost"

-Ryan

[ 02-26-2005, 09:08 PM: Message edited by: Shuck ]

[Barry Nave]

Shuck
Thats good stuff ;) :D

[Robyn]

Thanks guys
I am very suspect that it is a waste gate problem do to either s solenoid or a vacuum problem. truck also has an alternator problem too as in not working. I want to get a new alternator on the beast first so I have a good source of power to the system. The stator was hot but the gauge was barely above the red zone and the rest of the guages were reading a bit goofy. I beat on the alternator and the voltage came up as did all the rest of the instrument readings to about normal. I wont have the rig in my possesion till mid week so now all I can do is theorize. Low voltage can foul up a lot of things for sure and to get to far into diagnostics without first fixing the power source would be remiss me thinks. This rig has 250K on it but the engine is spotless top and bottom as is the tranny. no signs of a steam job. All the nooks and crannies that would be missed by a wash are clean and dry. Its been a desert rig so the lack of water and mud signs is not unusual. Rig was traded in to a small Gypo car lot locally. I drove it about 20 miles to get it good and hot to make sure it did not have any over heating problems as in cracked heads or such.
I flew to Southern Cal this week to buy a 95 sub that was supposed to be ready to go and have all sorts or new stuff on it (TRANNY) Not.
Had bad problems with puking antifreeze no heat and hard hoses. Engine had signes of hoses blown and it had a new radiator and belts. BAD HEADS me thinks. Flew home not at all happy. Guy was a jerk

[Robyn]

Well I got my 94 Sub Home and got to work chasing gremlins. The turbo waste gate hose was not hooked up as the rubber conector was gone and the tube was cracked. Fixed that and things got a bunch better. The rig was terribly hard to start and a survey of the electrical system revealed a bad ground cable on the right battery that was really messing things up. The former owner told me that it had been that way for the three years he owned it. All fixed now and all the gauges read right now as well ads the rig starts real fast and easy. Still getting an occational code light and the waste gate stops working. I am checking the vacuum pump and the sensors next as well as replacing the plug on the map sensor as it is broken and not staying pluged in tight.
Has anyone here ran a power chip on a 6.5. How well do they work??

[patrick m.]

"SIGH".... another one is headed down the road to becomming a "6.5aholic" :D


yes they work, very well in fact so well after a few weeks of running with a "good" chip, you will feel an uncontrollable urge to call Kennedy, (or any of the vendors here), and get another goodie.

BUT...first things first! got to have guages, Boost and EGT minimum.
and two rules that must be followed and the only way to follow these rules is with guages.

Dont exceed 12 psi boost without an intercooler
Dont exceed 1100 degrees EGT temp (sensor pre turbo).

let the fun begin :D