'88 GMC Suburban...

I test drove an '88 GMC Suburban today and want to get some input on a couple things...
When turning it over, it would halfway fire. I put MAYBE a quarter inch of
throttle pedal to it while cranking and it fired right away. What is the most likely cause???
When put into gear(TH700) at a stand still, it goes in fairly hard, not harsh, but abrupt. Shifts good under light, part, or full throttle. Kicks down fine. Fluid is good! Whets the best guess?
Idles pretty high. No tach but I would estimate 1000-1200 RPM. Could this be caused by the same thing causing the first issue which in turn is causing the second?
NP208 or NP241?
BTW, just under 180K on it!
Do ya need to know anything else?
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couple things...

throttle pedal to it while cranking

The ECM ignores TPS signal when cranking, so cracking the throttle just gave it more air, not more fuel. So, too much fuel or not enough air during cranking. I'd check the IAC pintle when you turn the key to run to make sure it's actually retracting. Other than that, FPR might be shot causing excessive fuel flow during cranking, OR a leaky injector is dripping into the intake after the vehicle is shut off and you need to crack the throttle to get enough air to fire the rich mixture.

harsh, but abrupt. Shifts good under

best guess?
Likely caused by the high idle as stated below. The higher the RPM the harder she'll dump into gear.

be caused by the same thing causing

Could be the rich mixture as stated above causing the high idle. IAC, CTS, FPR come to mind.

Not a clue.

She's a baby!

How much $$$ they looking for? Body in good shape?
Doc

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1988 and up is NP241 stock. I believe that the NP208 is directly interchangeable so if it torched, and they had one laying around....
~KJ~

a
of
gave
throttle
the
this
CTS,
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Somewhere in the $800-$1000 range...The body is rough, but not shot!
I am gonna sound like an idiot, but would you decipher the abbreviations for me, please Doc? I know a few of 'em, but just do 'em all if you would...
Thanx
| > I test drove an '88 GMC Suburban today and want to get some input on a | couple things... | > | > When turning it over, it would halfway fire. I put MAYBE a quarter inch of | throttle pedal to it while cranking | > and it fired right away. What is the most likely cause??? | | The ECM ignores TPS signal when cranking, so cracking the throttle just gave | it more air, not more fuel. So, too much fuel or not enough air during | cranking. I'd check the IAC pintle when you turn the key to run to make | sure it's actually retracting. Other than that, FPR might be shot causing | excessive fuel flow during cranking, OR a leaky injector is dripping into | the intake after the vehicle is shut off and you need to crack the throttle | to get enough air to fire the rich mixture. | | | > When put into gear(TH700) at a stand still, it goes in fairly hard, not | harsh, but abrupt. Shifts good under | > light, part, or full throttle. Kicks down fine. Fluid is good! Whets the | best guess? | | Likely caused by the high idle as stated below. The higher the RPM the | harder she'll dump into gear. | | > Idles pretty high. No tach but I would estimate 1000-1200 RPM. Could this | be caused by the same thing causing | > the first issue which in turn is causing the second? | | Could be the rich mixture as stated above causing the high idle. IAC, CTS, | FPR come to mind. | | > NP208 or NP241? | | Not a clue. | | > BTW, just under 180K on it! | | She's a baby! | | > | > Do ya need to know anything else? | | How much $$$ they looking for? Body in good shape? | | Doc | | > | > | > | > | > | |
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wrote:

Engine Control Module

Throttle Position Sensor

Idle Air Control

Fuel Pressure Regulator
HTH, Bret
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Thanx...I was real close! lol
| >:|| > I test drove an '88 GMC Suburban today and want to get some input on a | >:|| couple things... | >:|| > | >:|| > When turning it over, it would halfway fire. I put MAYBE a quarter inch of | >:|| throttle pedal to it while cranking | >:|| > and it fired right away. What is the most likely cause??? | >:|| | >:|| The ECM | | Engine Control Module | | | | >:|ignores TPS | | Throttle Position Sensor | | >:| signal when cranking, so cracking the throttle just gave | >:|| it more air, not more fuel. So, too much fuel or not enough air during | >:|| cranking. I'd check the IAC | | Idle Air Control | | >:|pintle when you turn the key to run to make | >:|| sure it's actually retracting. Other than that, FPR | | Fuel Pressure Regulator | | | HTH, | Bret
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What do you want this truck for?
~KJ~

input on a

quarter inch of

during
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I don't have it yet! I am looking at getting it. Somewhere in the $800-$1000 range! Do ya think its a good deal? It has got some Midwest cancer, but not too bad and definitely fixable!
| > | >:|| > I test drove an '88 GMC Suburban today and want to get some | input on a | > | >:|| couple things... | > | >:|| > | > | >:|| > When turning it over, it would halfway fire. I put MAYBE a | quarter inch of | > | >:|| throttle pedal to it while cranking | > | >:|| > and it fired right away. What is the most likely cause??? | > | >:|| | > | >:|| The ECM | > | | > | Engine Control Module | > | | > | | > | | > | >:|ignores TPS | > | | > | Throttle Position Sensor | > | | > | >:| signal when cranking, so cracking the throttle just gave | > | >:|| it more air, not more fuel. So, too much fuel or not enough air | during | > | >:|| cranking. I'd check the IAC | > | | > | Idle Air Control | > | | > | >:|pintle when you turn the key to run to make | > | >:|| sure it's actually retracting. Other than that, FPR | > | | > | Fuel Pressure Regulator | > | | > | | > | HTH, | > | Bret | > | > | |
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No I'm wondering what you want a Burban for. Mudding, pushing snow, daily driver. Like I said my 85' is for sale, and at the price I am hoping to sell for, a TBI conversion wouldn't be an impossible expense.
It depends on what you want the Blazer/Jimmy/Burban for what amount of rust is acceptable.
~KJ~

some
air
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