Okay I've got this engine miss that'* got me beat! :( I've checked the coils yesterday & they measured 14.3 Ohms on all 3 which I've been told is good. The wires are new last year from GM (8mm). I'm running Bosch platinum plugs but never had a problem with them before in my 3.8L Buick. I know I got a exhaust leak at the LH manifold to cylinder head. My question is: would a exhaust leak cause a engine miss? :?: Now I haven't decided yet to either machine the manifold for $45 (since GM doesn't use gaskets to heads) or install jobber exhaust gaskets! The T/B is clean & so is the IAC & MAP. No codes either! New O2 sensoe back in March (Bosch O2) - (cheaper than GM'* but better than anything else available up here). Now this miss usually more noticeable at idle than at higher speeds too. It disapears when you accelerate, then returns when engine RPM'* level off (say around 2000 - 2200 RPM'*). Any suggestions? :?:

What cylinder is the miss in? The Tech II should be able to tell you.

i had to get my fuel filter replaced like 3 times before mine went away.

That'* the problem! I can't tell what cylinder the miss is in because of the exhaust leak! :( I haven't done the fuel filter yet though. I don't think it'* fuel related though or the miss would be there all the time! I have been told that maybe TPS? IAC? Anybody else! I may borrow a Tech II yet to gain access to the vehicle sensor array, but like I said there is no codes! :?

Yeah, I would go with the Tech II. I don't think misfires throw a MIL unless they exceed a certain number.

Well the engine miss is gone now! The problem is I don't know how I fixed it! I just fiddled under the hood for about half an hour or so.

I once had an engine misfire because the insulation to the fuel injectors was burned through at the end and exposing bare wire. So I covered it up with electrical tape and it works perfectly. But there are many factors that can cause an engine miss. Mine is one of hundereds of possibilites. So check the wiring under the hood, maybe a bare wire is exposed. That'* just my experience with that problem.

Well I think I solved this "Miss" problem now! :? I'm changing out thr Bosch Platinum Plugs for AC Delco Platinums! I also replaced the fuel filter with a new GM filter! Also my remote starter wire was spliced into my Tach Signal wire from the ICM, well they didn't solder the connection! I'm going to fix that & hopefully my Tach problem will disapear too!

I would like to hear how the AC Delco Platinums work. I have Bosch +4 platinums now and will probably need to change my plugs early next year.

I have thought about going over to the RapidFire plugs from AC delco since they worked so well in my Jeep.

Our tune up tech at work told I should get about 160,000 KM'* out of these plugs! The Bosch Plus 4'* are not reccommended because Bosch uses a general heat range for their plugs I was told & the +4'* are not gap adjustable too!