HEAD AND VALVE ISSUE - Page 6

Service update:

Head replaced and the engine now purrs like a kitten.  Power and accelleration seems to be much better than it was the day I bought it new.

My dealer came through big time, and Hummer too.  Going to shoot for extended warranty.

Im glad the Hummer case manager talked me off the ledge when I was waiting for weeks for the part. 

Good luck all.

 
 
Glad to hear you're back in the good to go mode again..

Glad to hear it.  Be sure to let us know how the warranty thing works out

And good luck to you as well! May you continue to love your little Hummer and have no more real probs with it!  On the warranty thing, I found it was key to be consistant with those calls - until you have that LETTER in your hands!

quote:

ORIGINAL: H3X442

I had 2 more H3's come in with misfire codes and ordered heads for them. Larain60 let me know when you get yours in. It's bad enough I have to tell someone that there cylinder head needs to be replaced But this backorder situation makes it that much more harder to explain. Steve

H3X - Do the misfire codes produce regular OBDII codes? I bought one of those fancy shmancy OBDII code readers that I've used on my friends Explorer but not on mine yet.  It has the Database code summary built in.

The reason I'm asking because I've been having some suspicious conditions the past week or two.  I got a new belt tensioner and belt two weeks ago.  Since then (also when the temps dropped from 35 to 0) I have had a few instances (this morning) where the car started to sputter and the idle dropped to about 400-500.  It's been happening every couple of days.  The belt is fine, the tension is fine, but I'm starting to wonder if I'm getting this now.  I have 30k on mine and the manufacturer date is Oct. '05  It's starting to worry me.

Does a misfire cause the Check Engine light to come on, or only produce a code?

In most cases, Both to your last Question Mikey..

Mikey, I think the issue effects some differently. As I have stated in previous posts (much to the disbelief of some) I NEVER had a check engine light come on in the 2000 miles I drove it on my roadtrip which is when it happened. I got the OnStar report email containing the warning, a constant rough idle, and when I called OnStar to run a diagnostic, all they could say was it showed an "engine misfire code and an emissions isue."

Yup.  I remember you saying that.  That's why I asked.  I have a feeling I may finally be coming down with it, which doesnt make much sense considering mine was belt after the supposed date range.  I would like to just blow it off and say it's because the new built may be slipping, but I've driving almost 1000 miles since then and I think that's more then enough for a new belt to wear in.  I'll put the OBD scanner to it later tonight and see what it comes back with.  That's ALL I need now right

Mikey, your little Hummer isn't a hypochondriac is it?  Boy, you and Killer seem to have the duds of the bunch eh? 

Yeah, but keep in mind, we also drive our H3 more the probably anybody else on this forum.  In 16 months I have put 30k miles on it.  That's ALOT of driving.  If anybody we are the test dummies lol.  I take immaculate care of my vehicles I own and notice things most people wouldn't, and 99% of the time I'm right on the money with it comes to discovering and diagnosing repairs.  With the exception of this on-going differential issue, I've been right every time.  Now that I'm driving 100 miles a day to and from work, I'll really be working this baby lol.
 
I'll have to post a follow-up later and see if I'm getting any codes back.  I surely hope not.  At least I can bring it in to HummerMike now. I'll probably be his first customer lol.

I made a mistake.  Mine was manufactured in Oct. '05.

See my latest post up above under warranty contact info

Yes.  Very disturbing.  Real NICE customer service.  And then people wonder why Imports outsell American cars.

Well yes, they aren't going to give anyone anything that has not had this problem.

I'm not trying to be a pain but GM will take care of everyone.  Everyone just relax, it will all work out. 

Who is this guy???

Perhaps somebody that would like to protect the reputation of their company...................

quote:

ORIGINAL: H3Head

I'm not trying to be a pain but GM will take care of everyone.  Everyone just relax, it will all work out. 

 
You can't just make a statement like that without being a little more specific.  Is this your opinion or do you have some insight?

The obdII scanner should read a P0300 misfire detected but would also have a check engine lite. I also had another one with a head problem today
 

quote:

ORIGINAL: HummerGuy

quote:

ORIGINAL: H3X442

I had 2 more H3's come in with misfire codes and ordered heads for them. Larain60 let me know when you get yours in. It's bad enough I have to tell someone that there cylinder head needs to be replaced But this backorder situation makes it that much more harder to explain. Steve

H3X - Do the misfire codes produce regular OBDII codes? I bought one of those fancy shmancy OBDII code readers that I've used on my friends Explorer but not on mine yet.  It has the Database code summary built in.

The reason I'm asking because I've been having some suspicious conditions the past week or two.  I got a new belt tensioner and belt two weeks ago.  Since then (also when the temps dropped from 35 to 0) I have had a few instances (this morning) where the car started to sputter and the idle dropped to about 400-500.  It's been happening every couple of days.  The belt is fine, the tension is fine, but I'm starting to wonder if I'm getting this now.  I have 30k on mine and the manufacturer date is Oct. '05  It's starting to worry me.

Does a misfire cause the Check Engine light to come on, or only produce a code?

H3X442: I hooked my OBDII scanner up this weekend and have absolutely no errors, BUT whenever I come to a stop and take it out of gear, as I'm approaching the stop my idle dips below 500 RPMS until I come to a complete stop, then it boosts back up to normal, around 750 to 800.  It was happening almost every single time I stopped from maybe Tuesday or Wednesday until yesterday.  Today it didn't seem to do it, but it's 31 degrees as opposed to last week when it was below zero most of the time I drove it.
 
Have you ever seen that before?  Does the head and valve problem definitely produce an error code?

Mikey...It sounds to me like the Clutch switch maybe acting up..Look at the connections to the switch that's actuatated by the clutch pedal (near the clutch pedal under the dash)...I had an RX7 that would do exactly as you described and I found the clutch switch faulty....Disconnect the plug from the switch..Take an Ohmmeter and check out the switch, press and release the pedal and see if the switch opens or closes consistantly...

That's what I thought also.  I actually removed the clutch sensor plug you are talking about on Saturday because I was wiring a remote control switch for the KITT lights and had some of the wiring going through the harness, and thought, ok I'm going to plug and unplug it a few times to clean it. 

I haven't noticed it happen since, but I'm wondering A) is it possibly the cold weather doing it and B) wouldn't the PCM get an error code if the clutch sensor was faulty C) perhaps the + source wire that was going through the wires on the clutch sensor was causing some EMI in the sensor which was giving the PCM some bad signals.  That + is coming from the infamous AUX B+ wire behind the console.  That produces alot of power since it's tied right to the battery.

Since I did that the weather has gone from about 5 degrees to the now 31 degrees this morning.  It also started once they changed the surpentine built and belt tensioner pully.  It was doing it when I got the car back from service that night but that was also 2 days after I installed the KITT lights and ran that B+ wire tap.  There are bunch of variables, but I'm going to remove and replug that connector a couple more times before I leave work today and see if it does it anymore.  That may just be it.  Thanks buddy

My RX7 didn't throw a code either..The dealer at the time (Kenny Kent  in Evansville, IN) couldn't find the problem although they agreed there was a problem...Anyways..I started with the common element as it only happened once I pressed in the clutch when coming to a stop...Most the times the idle would dip so far and the car would almost stall, it did stall when the A/C was on...

Spray some contact cleaner on the switch and the connector.  (Deoxit is great)

I haven't seen contact cleaner is ages since Radio Shack stopped carrying it.  Do they sell that at regular auto stores or do I have to go to a electronics store to buy it?
 
That's exactly what it's doing FYI.

Go to an electronics parts house...Radio Sh!t don't have crap anymore..all they want to do is sell you a Sprint phone service...