just talked to my buddy and he said he reconnected the O2s in the original positions

 

I thought that was only for the new style iridium plug.

Never seen anything from GM stating that all plugs in all past LS1s should be gapped at .040.

 

GMs TSB 03-06-04-060A states that all LSx engines now require the use of a redesigned iridium tipped spark plug gapped at .040". The sole reason for the change was due to idle instability with the old platinum design, even with the gap closed down. I've been replacing the stock ACDelco plugs on Corvettes for years with NGK TR-55 plugs closed down to .045" to fix a rough idle concern. Rarely have I done a truck or F-body, as it seems either the Corvettes are more sensitive to the plugs for some odd reason, or the owners are just, well, you know

JCCamaro - it could be a fuel filter problem, but a clogged filter often acts very similar to a clogged catalytic converter. Usually it will restrict power, moreso in higher RPMs. Have you tried cleaning the MAF (with MAF sensor cleaner) and the IAC (with carb cleaner)?

 

no but i have a long weekend coming up so i will probably be trying all the different things people are suggesting

 

Marc 85Z28,

Thanx for the info on GMs TSB 03-06-04-060A ~ My 2000 SS is all stock & I just changed the plugs to Bosch +4 (at 52K) and it developed the hard start problem ~ come to think of it, the idle has also gotten rough. Looks like its time to change plugs again.....

 

Doing a little research on those plugs before purchase would have been wise. They don't work in almost all newer ignition systems, LS1 included. I regularly fight customers over these plugs. All too often I get cars with rough idles, poor driveability, and multiple misfire DTCs (I recently had an Acura 3.2TL come in with P0300, P0301, P0302, P0303, P0304, P0305, P0306, and P0316 ) - sometimes all issues. They never want to accept that their "best money can buy" $10 a piece spark plugs are causing the problems.

 

Marc,

Thanx for the advice ~ Ok, I've changed Bosch +4 #4458 out for the AC 41-985. It starts better, but not great ~ I'll have to try cleaning the MAF & IAC. As to the idle, its 100% better with the AC plugs. The Bosch had about 5K miles on them & looked quite dirty (carbon buildup), This is the first time I've had trouble w/ Bosch plugs, my LT1 in the Vette & Z/28 run fine with them. Also the 97 Vortec (GMC 1/2 Ton) loves them. Looks like these will get cleaned & recycled. I was turned off on AC plugs 10 years ago when I got one that the threads were not final died & another new one that had a hairline crack in the porciline.
Thanx,

Mark

 

Marc,

I cleaned the IAC & MAF ~ it made a big difference ~ the IAC was quite carboned up ~ The MAF did not look bad ~ I did not even know CRC made a special MAF cleaner.

Thanx

Mark

 

Changed the fuel filter, starts alittle better but some times it still acts like a carbed car and hesitates to rev when you first start it up, i rescanned the car and i'm throwing a code for coolant temp sensor, would the sensor make it hesitate like that on start up? I know a bad sensor can make the car run bad but after 20 seconds or so the car runs like normal.

 

If the coolant temp sensor doesn't report the proper temp the computer can't set the fuel/spark right and the car will run crappy.

 

I could see why the warm starts would be rough then, if its setting the a/f ratio as if the car is always cold, would probably explain why my gas mileage hasnt been that great either. (1 mile to drive to work, so I drive 4 miles with 4 starts a day)

 

Coolant temp sensors often fail reading full cold, somewhere around -40F I believe. Such an occurance would cause the car to run extremely rich.