Ok i finally got the fuel pressure tested and it came back good. also pulsed the injectors 1 by 1 with a tech 2 computer that my friend at the chevy dealer has. all fuel tests came back fine. do you guys think it could be a clogged cat which is making to much back pressure, cuz i noticed my rpms dont wanna come down sometimes or come down really slow. also the exhaust tip is very blackened now and the air comming out the exhaust is extremely hot. so how do you check the cat or cats for clogs without cutting it out?

 

A clogged cat would limit your RPM.

What was the background of your problem again...? Do you have another thread on this subject?

 

Kyle, this thread should be merged with the original to keep it all in one place. Here's the original:
https://blazerforum.com/forum/showthread.php?t=29702

 

What were the results of the fuel pressure and leakdown tests? Post the pressure and leakdown rate so we're all on the same page.

 

the rpm prob im not to worried about right now. im worried about the nasty hesitation im getting when i romp on it, if i take off slow the hesitation is not as bad. the pressure test was done by my mechanic friend and he said the results were normal. yes i made another post awhile ago. which can be deleted or combined with this.

 

Any time you work on a vehicle, you need to keep in mind that the last guy that worked on it didn't know what he was doing. That way you don't assume anything. We all know what "assuming" gets you. That's why I asked what the readings were. Fuel delivery is critical on these engines, and should be the first thing you check whenever there's a driveability issue.

 

I noticed my 98 hesitating about a month before the intake manifold (lower) developed a big leak. When I took it apart it was clear coolant was flowing to the fuel intake port adjacent to it.

Does your exhaust smell sweet like coolant?

 

well see i didnt assume anything. he actually had paperwork on what the readings should be and said that they were all normal. everything that breaks on my blazer i have him fix, he works for a gm dealer and did this there. so thats why i said i dont know what the readings are, he does the work. i already had the lower go on me and had that fixed. so if we rule out a fuel prob, what else could it be?

 

Done. I knew there was another thread, but had just enough time to reply to everyone else, not enough to go looking for the other thread. Thanks!

Without confirmation that the readings are above 60psi before starting, it is difficult to rule out the fuel pump...

 

i found the readings that i got when we pulsed the injectors each one was 58 then dropped to 48. called him and he said fuel pressure was 58. thats all the numbers i know.