H3T Barely made it home last night......

[Mr_Rich]

I've been putting my truck to a lot of use lately as a DD, and hauling stuff between homes in LA and SM. Last night I was planning on making my usual gas/ rest stop @Seaward Ave in Ventura. As I let off the acc on the offramp my truck suddenly lit up the DTC/ CEL and ran really rough. I just about coasted in to my gas stop. I shut down and filled up the tank. On restart the engine seemed to run smooth again and I decided to take a short break after parking my truck. I called OnStar and the lady said I had an Elec. TB problem. I made the decision to drive home, but I stayed on surface streets for a while before I was confident to get back on 101. The truck ran smooth until the last two miles from home. The engine bucked and snorted and I barely made it in the driveway. I'll be checking the codes and basics today. We'll see how it turns out.

 

[alrock]

Good luck, hope it is something small

 

[3Hummers]

or covered

 

[Kyle]

try cleaning the throttle body maybe?

 

[f5moab]

Do you have the 5.3L? GM had some problem with the TP sensor and the TAC module on those engines.

 

[Mr_Rich]

I didn't really do anything to my truck today. I started it up and it seemed to idle okay. I have an inexpensive code scanner I plugged in and it gave me an "Engine 7E8" which made no sense. No other codes. This is a base 3T with a 5M. Not sure if my Autotap program will work, but I may have to give it a try. It almost seemed like I got some bad gas. I checked my manuals and it looks like the fuel filter is a paper filter inside the fuel tank. I thought "PITA" when I read that. It should be an inline fuel filter like the other FI vehicles I own.

I pulled my 'Bird out of the garage as my DD for the time being.

 

[alrock]

I'd try again with the code reader or take it to Auto Zone or similar and have them give you the code. Could be gas, could be a bad connection somewhere, but it sounds like you need to get it figured out so you can be comfortable driving it.

 

[Mr_Rich]

I completed some much needed maintenance on my 'Bird today. I let the oil change interval extend to 7K miles; too much, IMO. That's done and now I'll concentrate on the truck. I've been needing to replace the power steering pump that I bought in Nov. I'm thinking I'm going to try and use a small pump I have to siphon some of the gas (?) at the bottom of the tank. Maybe there's some crud there. I'll also check the plugs and try some fuel system cleaner in the tank. This is a Calif. truck and isn't exposed to as much wet or corrosive conditions on the roads like I might experience back East. The engine compartment is pretty clean and I don't see how any electrical connections could be adversely affected.

 

[Mr_Rich]

I've changed the plugs yesterday with new AC's. Verified the gaps @ 0.040. There was nothing unusual about the plugs I removed; looked like normal wear on a 70K set of plugs. I cleaned up the throttle body. It looked clean on the air box side, but it was coated with black carbon on the intake side. All cleaned up. I started the engine up for the heck of it, and I was getting TRAC FAIL, STAB SYS FAIL, or something like that and the engine starts running rough. My HF code reader can't detect any codes though. I tried using my Autotap program on the truck but it looks like V2.0.1 won't work on a vehicle this new. I'm going to plan on replacing the PS pump to get that job out of the way. This truck may have to stay in the garage for a while. It will be easier to sort out the problems on my old K1500 at this point.

 

[05Mudiak]

2 things, check/clean MAF sensor and believe it our not check you battery terminals a bad terminal will make these trucks do all sorts of wierd things

 

[M22KLARS]

Can't believe nobody said anything about the battery terminals till now. :whaa: VERY common issue with the H3's.


Oh, also double check that everything you unplugged to do the plugs is plugged back in.

 

[Mr_Rich]

That's one of the hassles about our trucks; everything is electronic and inter-connected. I disconnect the air cleaner on my '98 Firebird to spray carb cleaner down the throat of the throttle body and no big deal. The throttle body is still cable controlled on that engine and disconnecting the MAF doesn't have a big effect. On my 3T that is obviously very different. When I started the engine two days ago after changing the plugs I forgot the MAF was still disconnected. I should've realized that would have a bigger effect than the same for my Firebird, for instance.
Today I finally got around to replacing my PS pump. It was a bit of a hassle. I had to make sure that I slop the threads on the installer/ removal tool with anti-seize. I also installed the pulley about 3/32" too deep on the pulley and had to pull it back off that same distance to keep the pulleys inline. It was a function of the tool I was using that was slightly different than installing the pulley on my K1500. Anyway, it's on and torqued to ~18 lbs./ft. The fluid that I drained out of the old pump was pretty nasty looking. More like engine oil that has gone 7K miles than the amber fluid it's supposed to be. I need to finish up tomorrow, weather permittting.
Alex: If you still want the old pump we can work something out to get it shipped to you....

 

[Mr_Rich]

05Mudiak: I did heed your advice and I cleaned the MAF sensor with electronic parts cleaner (alcohol spray). My air filter was pretty black and a dirty MAF was a real possibility for trouble.

 

[amrg]

Can't believe nobody said anything about the battery terminals till now. :whaa: VERY common issue with the H3's.


Oh, also double check that everything you unplugged to do the plugs is plugged back in.

I've been having issues with my battery terminals for awhile now! Hopefully next time I take to service Ill have em do it on warranty repairs! I can remove the battery terminal connectors without even having to unscrew them!!!!!!!!!! Its pretty frustrating while driving, my car keeps locking/unlocking the whole time. Everytime I clean the terminals and tighten the screws, issue goes away for a week or more then comes back!

 

[Mr_Rich]

I think all the work I did to my truck cured the problems. It was c-c-cold drive from north Santa Barbara county to LA last night. My truck was flawless and just "Hummed" right along...



This was a 70.5K maintenance procedure. I was kind of lulled to complacency for a while. I was forced to pay attention to added maintenance routines besides standard oil changes, etc.

 

[3Hummers]

Fingers crossed. Hope you got it taken care of.

 

[alrock]

Lots of good maintenance there. Those plugs look they were in decent shape so that's a good sign.

 

[Mr_Rich]

Lots of good maintenance there. Those plugs look they were in decent shape so that's a good sign.

I was encouraged by the plug condition. I kept them in order, 1 through 5, and they all looked pretty even. The coils seal the top of the head very well. The plugs are deep in the plug recess and can be challenging to remove once they're loose. A length of hose that fits over the top of the plug helps as an install/ removal tool.

 

[alrock]

My spark plug socket has a rubber insert that helps grab onto the plug so I didn't have too much of an issue with removing or reinserting, except that I would've rather had my hands directly on the plugs when starting to put them in vs. on the end of an extension.

I had a bit of rust on my plugs

 

[4speedfunk]

Like most hemi-headed motors (where the plug sits in a deep well in the middle of the chamber)...a shop vac is a good thing to have around when changing plugs. After you pull the coil-paks...suck the crust out of the well, before removing the plugs. This will keep abrasive chunks of dirt & rust from falling into the cylinder via the spark plug hole.

 

[Mr_Rich]

My spark plug socket has a rubber insert that helps grab onto the plug so I didn't have too much of an issue with removing or reinserting, except that I would've rather had my hands directly on the plugs when starting to put them in vs. on the end of an extension.

I had a bit of rust on my plugs

My spark plug socket has that insert too. It worked real well for the first one or two plugs and then started slipping out and staying on the plug I just unloosened. I didn't have my long reach needle-nose pliers handy and had to fiddle with the darn thing to get it out. It added a little bit of time, but I finally got the job done.

 

[Mr_Rich]

Like most hemi-headed motors (where the plug sits in a deep well in the middle of the chamber)...a shop vac is a good thing to have around when changing plugs. After you pull the coil-paks...suck the crust out of the well, before removing the plugs. This will keep abrasive chunks of dirt & rust from falling into the cylinder via the spark plug hole.

My Hoover upright worked in a pinch. I'm with you on this. Good advice though!