01 ZR2 Problems

I am new here, and do see a similar thread about a 91 4.3L below but I do not think that it applies.

Here is the Truck:

2001 S10 ZR2 Auto and Air
The truck only has around 10,000 miles on it.
And I just bought it from a used vehicle dealer about 4 months ago.

Here is the problem.

I am getting a nasty hesitation and stumble before it warms up fully and the problem *seems* to continue on low speed sharp corners and under load ( Going up hill )

I have taken the truck to the dealer about 5 times now. The problem seems to be getting worse yet no one can figure out what is wrong with it.

They originally told me that I had no compression in the number one cylinder, and then when they took the truck in to tear down the motor, they rechecked it and told me that I had full compression in all cylinders.

I took it to another mechanic the other day who told me that the truck works very good and its tight.

He pulled the number one plug and checked the compression, all was fine (180 LBS) but the plug gap was at .055 instead of .060 on the original plugs

He wet tested the plug wires ( Original Wires ) and they seemed fine.

There was some minor rust found on the rotor button so a new cap and button were installed.

Still have the problem though.

Any ideas ?

Tim

i have seen many of these symptoms. the most common problem was a bad mass air flow sensor. most of them did not turn the mil light on because the ecm didnt think anything was wrong. do the basics first. check for fuel, check for spark, and compression. you have spark and compression, so i would start looking at the fuel system for problems and/or ecm sensors.

i have seen many of these symptoms. the most common problem was a bad mass air flow sensor. most of them did not turn the mil light on because the ecm didnt think anything was wrong. do the basics first. check for fuel, check for spark, and compression. you have spark and compression, so i would start looking at the fuel system for problems and/or ecm sensors.


I have just finsihed running a Innova 3100 monitor on it and it gave me nothing.

I just filled up with 91 Octane Fuel which is what I always run in all vehicles with Lucas racing fuel treatment.

I have had the compression tested and it was 180 in all cylinders tested.

Wet Tested the Plug Wire and they appeared to be fine.

I do not personally know how to check for spark.

This may sound funny but something dawned on me tonight and that is that it may have started working bad after changine the oil and adding Lucas Oil Additive.

It also seem to work worse after every bottle of Fuel Injector cleaner.

The Dealer was of the opinion that it was likely carboned up, but 11,000 miles seems low to me for it to be carboned up.

However I am no mechanic.

Tim

i deal with carbon build up every day on low milage cars and do you know what the cause is? higher octane fuel! it burns cooler causing uneven combustion whcih causes carbon to build up. if your motor can handle 87 octane use it.

i deal with carbon build up every day on low milage cars and do you know what the cause is? higher octane fuel! it burns cooler causing uneven combustion whcih causes carbon to build up. if your motor can handle 87 octane use it.


Wow ... that is the first time that I heard that said.

I have always heard the opposite.

My truck is fixed now and the problem was my own for believing that the dealer really completed what they claimed they had.

I have been telling the other mechaniics I have taken the truck to what the dealer had tried to eliminate the obvious.

It turns out the they cracked the Distributor Cap when they put it on the truck and the truck had three spark plugs in it for a 5.3L with the Gap way out and the other side ( the hard side ) were originals that were carboned to death.

Drives like a new truck now.

Thanks for your input guys ... I appreciate it!

Tim

If you have any more questions, or just wanna chat with other zr2 owners, check out www.zr2.com . Everyone there is great, and there is specific info for our trucks, plus its acutally a higher hitting site for such a specific vehicle. Check it out.