Grey Goose

I am having one hell of a time trying to figure out what is going on with my car. Ok, here we go. The car is sputtering and backfiring while cruising. It doesn’t happen all of the time, just sometimes. If I’m sitting at a light and go deep into the throttle it will literally shoot flames out of the throttle body. Now if I ease into the throttle, the car is nice and linear as it moves through the power band. Now, if I’m on the freeway cruising between 60 – 70 the car is fine. If I roll into the throttle, it will spit and backfire just as though I was hammering the throttle from a dead stop. Now if I drop down out of overdrive and hammer the throttle, the car is fine. WTF? I have changed the fuel filter, cap, rotor, ignition module, and the distributor. The car keeps doing the same thing. I also played with the TPS and while the cart is idling and I move the switch manually, the injectors dump more fuel like they are supposed to. I’m at my wits end here guys. Any help or suggestions would be greatly appreciated.

BretD 88GTA

Mike,
How many miles are on the car now? Something that comes to my mind is what condition is the timing gear on the cam in?

MY '69 El Camino used to sputter and miss occasionally. Never could pin it down — checked the timing, distributor ...etc. THEN, one day I'm driving along and it flat out dies. Wouldn't restart.

At that point I had a pretty good idea of what the problem was and removing the timing cover confirmed it. The cam gear was wasted. To make it worse GM used to use a cheap metal gear with nylon over the teeth. The gear itself was worn almost smooth and I had a bunch of nylon pieces in the oil pick-up. How the timing chain stayed on as long as it did, I have no idea.

Glenn Duensing told me once that GM kept using that crappy gear design into the 3rd gen. motors. If your cam timing gear is worn, that could cause the intermittent misfires you're experiencing.

Just an idea.

injdinjn

Must be that time of year

Sounds like a timing problem to me too.

Thread hijack
I have a intermintent CLUNK when I start forward in my van. Mostly it sounds like its coming from just behind the right front seat, but there isnt anything under there. It must be traveling thru the chassis, problem is, I can't make it do it so taking it somewhere is a lost cause.

Dyno Don

iTrader: (7)

Check your fuel pump pressure. Anything less than 10# will cause that.

BretD 88GTA

Tom,
Are there any body mounts near where you think the noise is coming from? The reason I ask is that my truck occasionally makes a loud clunk while making right-hand turns. Feels like it's just in front of the driver's seat.

GM has a TSB issued on it and it's a problem with a body mount. GM's fix is to install a shim. I don't care for the noise, but it also doesn't do it often enough to motivate me to take the truck in for the fix.

TA

iTrader: (1)

Sometimes a bad coil will idle run at low RPM fine, but spit and cough at higher revs. Just a wild guess, but swap out the coil and try it.

TA

injdinjn

I kinda doubt its a body mount as the van has one long floor pan, but I ll give it a look.
One problem is the 1 ton suspension is so stiff its beyond anything I have to jack it up and wiggle things. The tires and bearings all are ok and the shocks are new but this occured before I changed them.
Thanks for the idea.

Grey Goose

Just wanted to follow up with a thank you to everyone for attempting to help me find out what the problem was. Turns out it was a bad coil which is funny because I wasn’t going to change the coil at all. I took back my core so I could get my deposit back and figured what the hell; it was spent money anyway so I picked up a coil. I plugged it in, sat it on the old coil, went for a drive, and problem solved. Let’s hope she stays together until I get my H2 back from the dealership and the $4,800 in warranty work is completed.

352,000 and still raising hell!

Thanks again guys,

-M

Russ-So Cal

Mikey, only 352,000 miles and the coil failed? I'd send a complaint to G.M. for building such a pile!

BretD 88GTA

I'm almost afraid to ask what happened to cause $4,800 in warranty work. Been doing some more off-roading?

1989GTATransAm

iTrader: (3)

If I remember correctly this might be the 2nd coil. IMHO I would try to get an AC Delco coil. Glad you found the problem.

injdinjn

Glad you found the problem, I missed that you hadnt replaced the coil.

Amazing that GM is doing warranty work on your H2.
A friend of a friend has, rather had, a 06 silverado and the paint was bubbling around the idiot brake light, he lives in Ridgecrest. GM says its not rust its a environmental issue and that warranty expires at 12K. So he traded it in on a titan. So for a $200 repair or less GM just lost a customer for life.
BTW, two body shops, including the one GM uses up there said it was rusting from the inside out.

Grey Goose

Well it’s an aftermarket extended service contact through Western General. The only reason I got into one is because I’ve been selling their Recreational Vehicle breakdown protection policies for a few years and have experienced first hand how they work their claims. I wrote my own automotive contract for a $500 (net cost) of which I sell the RV equivalent for between $3,000-3,500 (hey would you mind paying an extra 4 bucks a month for a little added security ;-). Horrible you say? More like extremely profitable wink wink. Anyway, before I took it to the dealer I called one of the claims adjusters I used to work with in Orange County and told him that I was planning on making a sizable claim. He went over all of the issues I had and informed me of what was covered and what was not on my contract. He then instructed me to take it over to Tustin Hummer as it is in his territory and he would be the adjuster they would call to authorize the repairs under the contract. I can’t say it would have gone as smooth as it did if I didn’t have a little inside help because when I dropped the truck off the service writer was almost apologetic because he just knew that the majority of my issues wouldn’t be covered. I received a call from my adjuster a couple days later informing me that all but three issues would be taken care of. Shortly after, the service writer called me and was shocked to say that almost everything was covered. He said that he had never seen this particular adjuster cut anyone any slack and that this was the first time so I should go and buy a lottery ticket. In any event, the repairs are in process, the truck should be done by Wednesday of next week, and I’m out of pocket my deductable of $100.

Items:

Cracked front right hub (covered)
Tweaked front right LCA (covered)
A/C control unit (covered)
Cracked water pump (covered)
Complete Sunroof Assy. (covered)
Speedo cluster (covered)
Bumper insert loose (not covered)
Handle on tailgate loose (not covered)
Driver seat cover flaps came loose (not covered)

injdinjn

Big rock about 1" below the surface?

The wifes aftermarket warranty on the Caddy was great.
Only used the one on the van once.
The one on the TA and the TBird sucked.

BretD 88GTA

Yep, Mike's been off-roading again.

The speedo cluster might have a TSB on it, so it may be a GM recall deal. I know that the full-size tricks have a problem with the stepper motors in the gauges. I received a letter from GM letting me know that IF I have a problem with mine, that they will fix it for free under the TSB.

There is a time limit though. It has to act up within a certain year/mileage restriction.

The big problem I'm having right now is paying $80 every 7-8 days in gas. It used to cost me $45 when I first bought the truck back in 2005.

A motorcycle for commuting is looking very appealing right now.

1989GTATransAm

iTrader: (3)

Just shows what a little inside information will do for you. Nice work on the warranty.

Bad analogy but it reminds me of some of the people on welfare who know how to work the system.

Guest

$4200 bj eh?

Grey Goose

Well lets just say that there might have been someone in an H2 very similar to mine out at El Mirage a couple of months ago that was challenged to drag race by some drunk clown in a hopped up 2500HD with a Duramax. From what I understand, there was a small rut in the middle of the lake bed that the H2 driver didn’t see because it was about 2 in the morning in addition to the fact that he was overdriving his headlights due to the speed he was allegedly traveling at. I believe that this might have contributed to the damage done to the running gear.
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Dude! If you're giving up that kind of coin for a buff and polish job... I'm your huckleberry!

injdinjn

When you first mentioned sputtering and backfiring,I thought you overloaded on refried beans.

injdinjn

Ok
one was a drunk clown
what was the other guys excuse???????????

Kevin91Z

iTrader: (1)

Once a week and you're complaining? I have to fill up once a week as well. Some people have to fill up every three days! When I lived in Aliso Viejo and commuted to Anaheim, it was like that, every three days. Instead of letting your vehicle get down to the empty mark, only let it get to 1/4 full. Then go fill it up. It wont cost as much that way.

injdinjn

Apparent 3rd gen sighting sat nite ~10pm 200ft s/o GG fwy at a place named after a Magazine

BretD 88GTA

That's exactly what I do. Truck = 25.5 gal. tank. Do the math, 18 - 19 gal. of fuel at $4.37 (for today anyways) per.

If I were still driving the GTA everyday, I'd be filling up every 3 days.


Ditching the K&N filter on the CAI in the truck for an AEM Dryflow, seems to have help the mpg. increase a tad. Also, installing the CAI in the GTA and losing the factory ducting and K&N filter seems to have helped it a bit.

injdinjn

Doesnt matter when you fill up, you still use x amount of gas.
When I worked in a gas station, $0.35/gal, I could never figure out why some people, mostly women, would buy a dollar or two of gas on a credit card. And they would do this every week.
Maybe they liked my personal service.

Grey Goose

Well a little birdie told me that you don't hit the bottom... but you give the sides hell. Perhaps this is why they were frequenting your station...

injdinjn

And this is a quote from Oprah
"Women prefer girth to length."

Kevin91Z

iTrader: (1)

Absolutely true, but since you're only filling up 3/4 of a tank, the total price is less. Plus, the fuel pump is cooled by the fuel around it, so the pump stays cooler when you have gas in the tank. The negative is you're filling up one-two days sooner than if you let it run to empty.

injdinjn

You should not run to near empty anyway.
You never know when an emergency might arise and you need a quarter to half a tank of gas.