My glow plug indicator (the curly wire) now stays on for at least 20 seconds before it goes out to indicate it is OK to start my engine. I have a LLY where the glow plug indicator used to go out in about 2 to 3 seconds. Ambient temperature is around 32 degrees F. Have I got a problem?

Yep. Go see your dealer :(

I know the search button was broken before, making it difficult to search - but I had the exact same problem with mine. Took it into the dealer a few weeks ago, and they figured out the glow-plug control module failed. Had to order a new one and it was on backorder. They actually just finished my truck this past Friday :) Works great now - I've got to be quick if I want to see the glow plug lamp on.

My glo plug module failed too,-:t brought it to dealer, they checked it out and said yep its bad,:mad: we'll order a new one and it'll be about a week and a half, they called me I brought the truck in, left a hour later ALL FIXED :) :ro)

No question about it zulu......On the lly, you have to be johnny-on-the-spot to even see the glow plug light....get 'er fixed!

You guys that had the module go bad. . . did you have any problems starting the truck or did you just wait until the light went out or what?

My glow plug module is out too. Every thing runs ok, called me on wed last week to let me know the part was in just can't get the truck in the shop. Mine caused a check engine light or so they say.

You guys that had the module go bad. . . did you have any problems starting the truck or did you just wait until the light went out or what?
The first couple times it did it, I waited the 45 seconds for the light to go out.

After awhile, I just waited ~5 seconds before cranking. Never had an issue getting the truck to start.

Mine was lightning fast until temps hit the twenties and teens at night. When its chilly like that it takes a couple of seconds for the light to go off, then she fires right up.

I noticed that on the wif's dmax the glo plugs took about 20-30 secs to go out at around freezing. I called the dealer and they stated that was normal ):h

what gives? I will need to call again...... :eek:

It's definitely not normal. Mine takes longer when the temps are below freezing, but still way less than 5 secs. When it's warm, I don't think it comes on at all.

Yep...you guys were right. I just picked up my truck from the dealer and they ordered an "upgraded glow plug module". In the interim I'm just going to steamboat to five seconds and start the damn thing.

Upgraded? meaning the General has improved? The wif has her Max in today to get it checked out......

I had the 20 second problem (no matter if it was 20 below or 20 above (celsius))and it took a lot of convincing to get the dealership to take it in, in fact I used this forum's postings to help convince them that the controller was the issue. I pick it up in an hour, talked to the service rep and everything looks good. I will update tomorrow whether it is working like it used to (2 seconds max).

Update, just want to confirm that replacing the controller solved the problem. So, if you have this problem be adamant and don't let them tell you that it is normal, it isn't. Even if the temps are around freezing you should see the gp indicator for max of 2 - 3 secs.

I hate it when I get in my wifes Grand Prix and wait for the glow plug light to go out. Wow...

I have had my truck since March and after 2 months I experienced the problem that you are discussing. It was identified as a PCM failure. My dealership is not willing to change out the module until GM finds out what caused it to fail in the first place. Those of you who have had it replaced under warranty - has the problem re-occurred?

My glow plug light will not go off in the mornings or if it sits for along period of time during the day, but I have no problems starting it at all. It's going in next week to get fixed along with my DVD player that doesn't work. I will let you no what I find out...

Mines in the shop getting a new glow plug module cause it would not turn off in the mornings. Caused a check engine light to come on though.

Trucks built before March can have a problem like this. It is actually setting a code (U0106) but not turning on the engine light...except for vehicles with california emissions the engine light is turned on. With the U0106 code set, the GPCM is not functioning and your glow plugs are not glowing.

So...if your wait to start symbol stays lit for more than 5 seconds, and you have a yellow dot on the top of your GPCM, you need to contact the dealer to get a new module ordered (it will have a green dot on the top). While you are waiting for the new module, you can restore functionality to the GPCM by disconnecting the 12 way connector and the B+ connector on the GPCM for about 30 seconds and then plugging it all back in. The U0106 code will clear on its own once the ECM can start talking with the GPCM again.

Thank-you JimmyDel. When I picked up my truck from the dealer they told me about the exact code that you have in your post. They claimed they didn't know what it meant but ordered a new GPCM. How come you know about this and they don't?

There is a PI in the GM Service Information that describes this problem and what to do about it.

Bump...If your "wait to start" symbol stays on for more than 5 seconds, and your truck was built in December (03), January(04), February(04) or March(04), you may have set a U0106 code. Have the New module ordered and installed...if there is a delay getting the part, disconnect both the connectors on the module for 30 seconds. This will reset it and it will function normally again for a couple weeks.

Where is the module located? Need to reset until wif can get truck in to shop......

Thanx, Ralph

Took my LLY in last week and the module tested bad. They ordered in the new part and installed it today and it solved the problem.

The module is on the drivers side of the engine, near the top and near the back. It is about a 3.5 inch square black plastic module with a yellow paint dot on the top. There is a round connector, and a rectangular 12-way connector going into it. Written on the top (in letters difficult to read) is Glow Plug Controller 8-Cyl.

Thanxxx JimmyDel

As stated above there is a PI (preliminary information) document addressing this. The fix is to replace the glow controller. The plugs are not "on" this entire time, the controller isn't communicating properly with the ECM. The fix is to use the 2005 glow controller # 97379635.

Refer to document #1578717 dated 12-17-04 to help the dealer find it.