When I am driving my GMC Envoy SLE, I notice that from time to time, there is a sudden slight*****. It is most noticeable whenever I am approaching an incline.
have the same problem?
Friday, October 7th, 2011 AT 2:31 PM
Sounds like a spark plug or coil breaking down under load. Could also be something with the transmission like the converter going in and out.
You need a shop to at least road test it for you to verify and get a bid.
Friday, October 7th, 2011 AT 2:40 PM
Went thru same deal w/ '03 Ford Escape
Repetitive, fast hesitation, lasting 1-2 seconds, more evident climbing a incline, while slowly administering gas. Random or none on level ground.
---No codes --- cleaned 1st, and/ or replaced the following
New Plugs. Then "genuine plugs". Bah-Hum-bug, nothing WAS wrong with the other new ones, I just installed!
Boots and springs
A new IAC (JUST for Giggles!)
Mega Vacuum leak search several times.
Fought with wife many times over situation, 2+ months!
I really hated taking off the "Plenum" so many times to access the other 3 cylinders
Each part seem to fix it for a day or two.I did not mind replacing the suggested parts, as I am all for "PM" and she's got 100,000 miles on her rig.
The final cure was #3 misfiring (lucked into the correct cylinder) I was gonna swap a new coil pack down the line, till it stopped HESITATING. THEN I CAUGHT A BREAK!
#3 was the ticket!
I had tried to get the Technical school to ride me with their portable machine---things did not work out, with their schedule.
I went to a salvage yard to get a used pack ($10) to swap around, TO SEE IF THINGS CHANGED, then I was gonna buy a new one if solved the problem.
So happened, the salvage yard guy had a machine, in a stored code, it said #3 had misfired. My little scanner could not tell me that!
Runs perfect now, with the New $79 Coil Pack!
THE OTHER PARTS I PUT ON, I SORTA CONSIDER PREVENTATIVE MAINTENANCE, (I NOW HAVE SOME SPARES FOR FUTURE TESTING. HER RIG DOES HAVE OVER 100,000 MILES.
I WILL DO ANYTHING TO AVOID THE DEALER OR A BIG SHOP, I FEEL NOT ONLY DO I HAVE IF FIXED, EVEN WITH THE UN-NEEDED PARTS (NOW INSTALLED).I'M SURE I CAME OUT TO THE "GOOD", COMPARED TO, IF THE DEALER REPAIRED THE COIL ISSUE ALONE!