big time hesitation..need help

[BigCutlass]

ok guys...i have a big hesitation from a stop where the car seems like its struggling to stay alive..then once it hits 5-10 mph it takes off with no problem...changed out the plugs and wires..still there...any ideas? the coils are fine. could it be clogged injectors? do i need to have them flushed? my regular mechanic is outta town right now..the guy i took it to this time said could be throttle positioning sensor. but any ideas would be helpful.

[white96six]

could be lots of things but sounds like the TPS to me too. put a voltmeter to it if you have one. not sure on these cars but generally voltage when closed should be around.5 of a volt.hope this helps.

[BigCutlass]

<blockquote>quote:</font><hr>Originally posted by white96six:
could be lots of things but sounds like the TPS to me too. put a voltmeter to it if you have one. not sure on these cars but generally voltage when closed should be around.5 of a volt.hope this helps.<hr></blockquote>

alright...thanks man..my dad has one so i guess will go test it..thanks for the tip.

[Guardsman]

Also, check the MAF Sensor. I've been doing some diggin on them, and one thing I found was a tech article saying that instead of going bad, our type of MAF sensor (Hitachi) can slow down. First thing, is tap on the MAF sensor while the car is idling. If the engine starts stumbling while you are tapping on the MAF sensor, it's definitely bad.
The second check requires more technical equipment. If you can get ahold of a full-function scanner, one that will show the MAF frequency, pull the MAF connector, and gun the throttle real quick, and see what reading it gets (the PCM will use a default table when the sensor is disconnected). Plug the MAF sensor back in, and gun it again. Then, compare the readings. If the MAF sensor reading is off by 30% or more from the default tables, it's bad.

[BigCutlass]

<blockquote>quote:</font><hr>Originally posted by Guardsman:
Also, check the MAF Sensor. I've been doing some diggin on them, and one thing I found was a tech article saying that instead of going bad, our type of MAF sensor (Hitachi) can slow down. First thing, is tap on the MAF sensor while the car is idling. If the engine starts stumbling while you are tapping on the MAF sensor, it's definitely bad.
The second check requires more technical equipment. If you can get ahold of a full-function scanner, one that will show the MAF frequency, pull the MAF connector, and gun the throttle real quick, and see what reading it gets (the PCM will use a default table when the sensor is disconnected). Plug the MAF sensor back in, and gun it again. Then, compare the readings. If the MAF sensor reading is off by 30% or more from the default tables, it's bad.<hr></blockquote>

when you say "our type of MAF sensors", are you referring to all GMs or F-bodies?

[HiArrival]

man, I just had a similar problem. I went through the whole deal changed everything for normal (plugs, wires, filters, top end engine cleaner, checked sensors). It all came down to a clogged cat. Only way I found it out was that one of my buddies happen to have one of those scan two deals the dealerships use and the readings between the O2 sensors, the one in front the cat compared to the O2 sensor after the cat. Save some money and check out your cat before you start screwing with the sensors. Just my 2 cents. Good Luck

[ September 29, 2003: Message edited by: HiArrival ]</p>

[Guardsman]

<blockquote>quote:</font><hr>Originally posted by BigCutlass:


when you say "our type of MAF sensors", are you referring to all GMs or F-bodies?<hr></blockquote>

All 99+ cars w/ the 3800 Series II. They use the Hitachi MAF Sensor.