Ok, no offense guys, but I have always had Dodge trucks. I just purchased a 1996 blazer 4wd with 4.3 vortec and 167,000 miles as a run around car. If I had looked at the issues that these are known for, I might not have taken that plunge! It has a slight misfire, and the check engine light is on intermittently, it also has the classic hesitation after accelerating from a stop. I thought it probably just needed a tune up, but we just did plugs, wires, air filter, fuel filter and oil. We are going to flush radiator later today too.

My question is, after looking into this forum, the culprits might be the cat, sticking poppets, mass air flow sensor, egr valve, tps, or maybe lack of dielectric grease between the icm and backet. That's a lot to do, and I was wondering in what order would most of you pursue these issues. I am trying to get a plan of action together so we can tackle all of these things today and tomorrow. I have never worked on the vortec, aside from the spark plugs and oil the other day (still have the bruises on my arms, seriously not a user friendly motor to work on!) What's with the hidden plug? Nothing like my good old 318! Anyway, could someone point me in the right direction for the best starting point?

Oh, and I smell antifreeze when I walk in front of it, but see no leak. (husband rolled his eyes at me until i showed him several other complaints online about it!) How hard is it to replace that gasket on the intake manifold? Also, the oil lines are all tarred up with old oil, but I see no spots where I park it. Is there a way to fix them without replacing them with the same stupid design? Otherwise they will just fail again, right?

Please tell me these cars are worth all the aggravation! It sure is comfortable for me and the kids. However, with all these issues, we might have to go back to my 97 ram 1500 farm truck. At least the only real problem the seem to have is a weak tranny! Thanks for any help!

 

this one is easy.."Also, the oil lines are all tarred up with old oil, but I see no spots where I park it."

what i did was very carefully remove aluminum crimped ends and then bought 4 feet of high pressure tranny line and some adjustable clamps. been fixed that way for years.
the alum crimps flex with heat and you get seeping oil on the ends.

this is probably too late but i always found the easiest way to the plugs was thru the wheel well...maybe that helps??

as far as misfire i would start at simplest and move from there. i had random misfire code..checked egr maf and the tps...turned out to be bad dist. /rotor in the end. you will read that the misfire is a total p.i.t.a. to hunt down.

one thing i have learned here though is one of us always seems to have an answer.
sorry i couldnt help more.

 

The intake manifold gasket job is a decent sized job its not too hard just time consuming. If your misfire is a random misfire check the distributor drive gear for wear. I have a 2000 s10 and a 97 blazer both 4.3's that had the same problem and it was a bad distributor drive gear both times.

 

Ok, here is an update on my blazer situation. The antifreeze smell turned out to be just a bad radiator, it blew one morning while my husband was driving to work. (now he believes me!) That is fixed and no more smell.

As for the misfire problem, we have done a few things since the last post. We removed and cleaned the egr valve, and the maf sensor. We took the ignition control module off and applied dielectric grease to it (it was completely dry). We also used a bottle of injector cleaner. I crawled under it to check if the plug to the wiring harness was dirty or damaged on the rear crossmember, it was fine but we cleaned it anyway. Banged on the catalytic converter and no rattle. took out O2 sensor before the cat, no change still hesitating. Then I found a disconnected vacuum line by the battery side of engine compartment. Reattached and then it had more power, but still hesitates and cel flashes sometimes.

Last week I was meeting a customer to pick up a rabbit in a parking lot, and I noticed that even though the truck was off, my gauges were still on. The temp, rpm, and fuel gauge were still reading! So I turned the key on but did not start it, then back off and the gauges turned off. On the way home it drove PERFECTLY! Don't understand the cause, but I went to autozone and they cleared the p0300 code and it has not returned. As long as you make sure the gauges are off it drives like a new car! I guess there is a short somewhere, how would I find it? Also the temp gauge is always really low like 150 or so, and he replaced the thermostat with the radiator and no change. Could this be related?

 

I would say there was a problem with the ignition switch not disconnecting properly. You can read up on that by clicking the ignition switch link in my signature.

 

Well it was a loose coil pack this whole time causing the problem! We replaced it and it runs like new! Just thought I would post this to maybe help others in the future.

 

What exactly do you mean by a loose coil pack?
I have a similar problem. Are you saying that replacing the coil cleared the gauge and misfire problem or just the misfire?
Don

 

Sorry for the long delay. No I still have the gauge problem. It drives like a new truck now though. Keeps blowing a fuse, the courtesy one. That's the next thing to track down.