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Discussion Starter #1 (Edited)
OK it doesn't d o this all of the time but occasionally when breaking hard to a stop when i go to take off again the car hesitates and stalls and then is really hard to start again..... also if i run the car and it gets up to temp shut the car and then go to restart the car again a minute later its really hard to start.... it has juice and cranks but takes like at least 3 min to start when it does this can anyone help me on this one?


Also the car seems to shift eratic sometimes. when on highway cars rpm will fluctuate from 1500 to 2500 sometimes at normal driving conditions.. could this be some kind of sensor and if so how much is it to replace?

Detroit i notice you know a lot on here any help from you on these issues?
 

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Discussion Starter #4
thanks. have you had this problem before too?
 

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Discussion Starter #7
Awesome guys thanks a lot any suggestions on the tranny shifting weird i think that may be a sensor
 

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Sounds like a fuel filter ie..lack of fuel volume.
If you haven't changed it in awhile change it first.
An easy way to diagnose that would be when it won't start.
Cycle the key to on 7 or 8 times,hesitating for a few second at "ON".
Then see if it will start,if it bust's right off then change your fuel filter and put some Chevron with Techron fuel system cleaner in it.
Fuel filter could cause all the issues you mentioned-shift error sounds more like engine not getting enough fuel and trans is reacting.
That or the MAF(never remove MAF screen-you will need a trans eventually if you do) as the MAF is what calculates load for the trans.

MAF's hardly ever go bad and are misdiagnosed regularly-clean it with electrical system or MAF cleaner at every oil change-ESPECIALLY if you use a K&N filter. When you reoil the K&N allow it to sit overnight to drain off excess oil.
MAF cleaner is available at AZ.

Not likely,but it could also be the fuel pump output low due to a bad check valve.
It leaks off causing the hard start,and under load drops the pressure.
Not sure if it's common on GM's but I see it on Fords every other day.
Easiest way to diagnose from home is hookup a fuel pressure guage,cycle the key to build up pressure and walk away for a few minutes. Pressure will drop a little due to heat if the motor is hot,but otherwise shouldn't drop more than a couple psi.
For a pressure drop diagnosis run the guage behind the cowl and onto the windshield where you can see it.
Drive down the road in first gear hitting 5k+ rpm and look for a substantial pressure drop.

Hope some of that helps,make sure to keep your fuel filter changed at regular intervals. The type/design of these pumps make's them very susceptible to failure when pushing against a restriction.
Oh yeah,and don't buy wal-mart gas.
 

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Do yourself a favor the fuel pressure regulator has a vaccum line attached, you can uplug that line, and if you get gas coming out of it, you need a fuel pressure regulator. There are other ways of testing, but that's the most obvious one. It could seem like your transmission is going screwy, but until the initial problem is fixed, don't worry about it yet. But let us know how you make out.
 
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