fall on face 93 gmc burban 4x4

truck has less then 200 k the truck never really had any major issues in the 2 years I
have owned it. since it was older truck i replaced some of what i thought was needed
parts. long list lol "spark plugs, wires,cap and rotor, oil, fuel filter, fuel pump,MAP
sensor,egr valve,TPS,ignition coil, the only 02 sensor, and i believe the temp sensor son changed.verified
all vacuum lines to the engine and the 2 barrel throttle body". i have cleaned the
throttle body best i can with out taking it completely apart. my son took the cat off the
truck and has a cherry bomb muffler only on it.i have not done a transmission filter kit
yet because i don't know when the last time it was done and have seen horror stories
about doing one that has never been done or a long time between. my big question is
when the truck is in neutral or park it revs up nice and sounds very good to my ears.
when i place it into drive and punch the go pedal it falls flat on its big arse , i can get
up to highway speeds but i have to go slowly to get there.what else could cause this
truck to do that ? thank you for all the help i can get on this big beast. i will try just
about anything before i send it to the junkyard.
 

eightshot627

Well-Known Member
Sounds fuel related. Specifically lack of volume of fuel. In neutral it doesn't require much volume to get the rpm but under load it does. A 93 pick up I had I had on a trip from Connecticut to Delaware it went from running fine to crawling up to speed. Not fun at the last tollbooth in New Jersey. Same symptoms a fuel filter fixed it. I would start with another fuel filter and then check fuel pressure.

Good luck,
Walt
 
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93gmcburban

Member
my son had it for a little while and i hink he changed the fuel pump also but it could have been a cheaper one lol. what should the fuel pressure be ? i know on my 97 tahoe it runs around 60 to 70 psi.
 

northcreek

Well-Known Member
truck has less then 200 k the truck never really had any major issues in the 2 years I
have owned it. since it was older truck i replaced some of what i thought was needed
parts. long list lol "spark plugs, wires,cap and rotor, oil, fuel filter, fuel pump,MAP
sensor,egr valve,TPS,ignition coil, the only 02 sensor, and i believe the temp sensor son changed.verified
all vacuum lines to the engine and the 2 barrel throttle body". i have cleaned the
throttle body best i can with out taking it completely apart. my son took the cat off the
truck and has a cherry bomb muffler only on it.i have not done a transmission filter kit
yet because i don't know when the last time it was done and have seen horror stories
about doing one that has never been done or a long time between. my big question is
when the truck is in neutral or park it revs up nice and sounds very good to my ears.
when i place it into drive and punch the go pedal it falls flat on its big arse , i can get
up to highway speeds but i have to go slowly to get there.what else could cause this
truck to do that ? thank you for all the help i can get on this big beast. i will try just
about anything before i send it to the junkyard.
Did this problem start after you did all the work?...Mike.
 
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93gmcburban

Member
no it has been this way for a little while. son didn't want it no more cause of gas milage sucks on it lol. i have had many old school GM trucks, when i press gas to hard from dead stop or even a passing gear it falls flat and almost starves and stutters
 

northcreek

Well-Known Member
What kind of injection does it have TB or port ?
 

northcreek

Well-Known Member
Okay, there are high and low pressure fuel pumps depending on the type of injection. So you have TB and should be good with a low pressure pump.
Man, it could be anything at 200K. I had a 92 and a 97 and at high miles they had drivability problems and I had to replace the ECU's on those.
As suggested earlier I would check the fuel pressure to eliminate that possibility.
 
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93gmcburban

Member
had someone tell me it could possibly be trans ? when i accelerate slowly i can feel the shifts and it doesn't seem to be slipping. and if book says correctly the fuel pressure should be between 9-13 correct ?
 

northcreek

Well-Known Member
I seem to remember it being around 15 psi so it's probably regulated to 9-13 psi. It doesn't seem like a trans problem to me, you would hear the engine screaming while trying to accelerate.
 
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93gmcburban

Member
Thank you for all the information that you've given me. I will break out the fuel pressure tester and see where I'm at. Also change the fuel filter and see. Thank you again
 

MRRSM

Lifetime VIP Supporter
You mentioned cleaning the Throttle Body... did that include replacing the Air Filter as well for an added performance bump?

With your mention of sincerity about wanting to keep your 1993 Suburban... I thought you might want to know that eBay has a "Best Offer" listing of ALL THREE OEM GM SHOP MANUALS that are probably worth their weight in Gold for your 26 Year Old Vehicle.. offered presently for a Buy Now Price at under $60.00.


87988
 
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93gmcburban

Member
Nice price for the good manuals. It has a new frame air filter maybe 6 months old. After the fuel filter change she runs gets up to speed fairly quick for having just 2 fuel injectors
 

BrianF

Well-Known Member
Glad you got it figured. I am still going through the trials and tribulations of getting my 1993 C1500 up to snuff. My stumble was traced to a failing EGR solenoid and valve.
 
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93gmcburban

Member
yeah the egr and the valve far it was cheap and easy to replace.


only other issue it has is when i start it first time in a day and if i drive to far and engine gets to normal temp, and when i kill it the key turns and all my dash lights come on but will not crank. if i wait a awhile to where it cools a little it fires back up or if i have someone jump start it \. the battery has been tested at autozone and the starter has been tested. one of those bang your head on dash things lol
 

BrianF

Well-Known Member
Thankfully the electrical on mine is somewhat sorted out. I pulled a random relay from under the dash and the parasitic draw disappeared....
 

LVJJJ

Well-Known Member
If you've got the stock air filter setup on it and it has that boxy chamber with a 3" hose or pipe, junk it and get a 4" dryer pipe and hook it direct from the fender to the air cleaner inlet. Made a huge difference in power on my '94. Plus I added another 4" inlet on the other side, dryer pipe coming in from other fender. Also took out all the little doors and fittings at the inlet.
 

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