I have 2000 blazer trailblazer edition can someone please tell me where the fuel pressure regulator is located on my engine please?

Ok to the point I have a 2000 blazer trailblazer edition 4.3 automatic 4x4 with 127000 mi. The problem engine runs smooth at idle but when you drive it it hesatates and stumbles between shifting into 1-2 and again 3-4 but not 4-overdrive. This problem occurs when it's hot or cold (engine temp) for about 5-6 miles then it stops until the next day or it sits for like 12 hrs. then it will start all over again. Also when driving down the interstate once you get to 60 mph it starts stumbleing and studdering even with cruise on, and it will do all these things when its placed in neutral or park. Now things I have tried new plugs, plug wires, cap and rotor, scanned comp. (nothing found), fuel pressure check pressure was 63 psi at idle and 67 psi when reved, cleaned TB and IAC no vac. leaks. So could this possibly be a injector problem? All input and opinons are greatly appriciated.
Thanks

Thats either a tranny or sensor issue man. Any trouble codes?

Under the intake plenum (upper intake manifold).

Have you cleaned the MAF sensor?

Have you checked the output from the TPS sensor? I have seen a TPS sensor wear out in that one place where it always rides while cruising along. This can cause all sorts of problems. The output from the TPS sensor should read ~0.5V at idle and ~4.5V at WOT and be a smooth transition between these values. Read across the sensor by back probing the connections using the sensor ground and sensor output. This will give you the exact value that the PCM is seeing. If, at any position in the throttle angle, the value drops off, the TPS sensor is bad and needs to be replaced.

Mine shifts real hard almost like it has a reprogrammed shift in it for racing at times mainly in the morning. It doesnt do it any more since I cleaned the sensors up. MAF crank position cam position plus replaced the cat. I did also clean the aft O2 sensor. My service light never came on for about 3 months and when it did it was P0300 random misfire.

NO trouble codes present I just checked it to day and nothing. I will check the TPS as soon as I get done with this reply. Also what's the best way to clean the mass air flow with out damageing it?

They have a spray cleaner for it at the auto supply. Be extremely careful of the wire in it since it is very delicate.

DING DING DING I think we may have a winner I just checked the TPS and @ idle it is .5 V but @ quater throttle it can't make up its mind if it's 2V or 3.2V or 1.3 V so that's got to be a dead give away that it's bad. Thanks Swartlkk

well crap the TPS did not work nor did the cleaning of the MAF. :mad: So open for more opinions if anybody has an idea. Is there a way of diagnoseing the fuel injectors without tearing the top end appart?

Have you cleaned the EGR valve?