So very true. I have had one too many go-arounds with others on this site about Bosch plugs in the past. I would not use them if they were given to me. I have seen them fail way too quickly and in one case, one lost a ground strap (had 3 more LOL) taking a valve out with it. That part sucked for the vehicle's owner that did not want to listen to me. Plugs only had 7k miles on them. Bosch claimed operator error when confronted about the problem and subsequent damage.

And do not get me started on Bosch O2 sensors for GM vehicles.

 

No sarcasm here, just my findings over the past 30+ years making a livin'. It's true, as long as you don't install them in an engine, they're GREAT!

 

OK guys sorry it's been a while but have been busy. Here is an update on my problem I went back and replaced the spark plugs with OE plugs AC Delco, new TPS, new MAF, and changed the cat, guess what still have the same dang problem but now it is so bad when you crank the engine it idles perfectly but as soon as you press the gas it starts spuddering bad. Also new fuel filter, I had fuel pump checked it is good. So could it be the whole fuel injector assembly? I have run injection cleaner thru it for 2months now and it has gotten worse. Please please help me

 

What were the results of the fuel pressure test? What was the leakdown rate? It must pass BOTH of these tests.

 

Water in the fuel?

 

I don't remember what the leak down rate was my friend did it for me @ a the chevy shop after hours, but I do remember the pressure was like 63p.s.i @ idle and 67 p.s.i. when reved up. I thought that there might have been water in the fuel so I dropped the tank when I got it down close to empty and drained it then let it sit in the sun to dry out completely this didn't help either but it was a good idea considering it acted like it had water in the fuel. My friend @ the chevy shop mentioned something about the injector distribution block, injectors, or the little black tips that go into the intake could be faulty. Could this be true??

 

Your friend at the chevy shop should know that GM does not publish any "engine running" fuel pressure specs, there are far too many variables involved. Key on, engine off, fuel pump running: pressure must be 60psi to 66psi and must remain above 55psi for 3 to 5 minutes after the pump shuts off.

 

I have done a pressure test myself and with key on the pressure is 63p.s.i. after five min. the pressure fell to 59 p.s.i.

 

Any other options?

 

If you put it in drive, and brake torque it, increasing the RPM very slowly, can you duplicate the problem?