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View Full Version : Help! 2.8 No acceleration


Boogieman
08-08-09, 05:49 PM
Hey Guys...I need some help. I have an 88 S-10 P/U 2.8 4x4.
The engine runs great in park or neutral (Jasper engine with 25,000 on it)Tranny rebuilt a few weeks ago.
My problem is no power. When going up a hill on the highway, it won't go above 40, it bogs down. On straightaways, I get a little more power if I back off on the gas.
I have replaced the Cat/Muffler/injectors. I tried to replace the o2 sensor, but I couldn't loosen the old one and I didn't want to snap it.
My mechanic cannot figure it out.
Can anyone help?

Thanks....
The Boogieman
Tink
08-08-09, 06:22 PM
Was this problem there before the tranny rebuild? Are you getting a check engine light at all? On the Jasper motor, are you running your orginial throttle body and if so, has it ever been rebuilt?
Jay-Sliver
08-08-09, 07:16 PM
TPS?

Jay
Danzcameo
08-08-09, 09:17 PM
Sound fuel related to me,filter clogged-pump failing.
readjust valves-one and a half turns after lash! weak valve springs
Boogieman
08-08-09, 10:11 PM
Sorry if I'm in the wrong thread...It's my first post...

No check engine light
Original Carb/never rebuilt
Has been a prob for a while
Boogieman
08-08-09, 10:20 PM
Sorry, no Carb, it has a TBI
Bone Crusher
08-08-09, 10:26 PM
Sorry if I'm in the wrong thread...It's my first post...

No check engine light
Original Carb/never rebuilt
Has been a prob for a while

Dont worry I took care of the double post and cleaned things up. Everything is in the right section now.
Jay-Sliver
08-08-09, 10:36 PM
When was the last time the fuel filter was replaced? Sometimes the simple things are over looked.

Jay
Boogieman
08-08-09, 11:57 PM
I don't think the Fuel Filter has been replaced at all. ... I'll have to find where it is first, but I will try changing it..
Tink
08-09-09, 08:26 AM
Fuel filter should be in the fuel line running along the frame rail.

You can also check the voltage of the TPS to see if that is causing the problem. TPS volts should be close to 0.42 V at closed throttle and rise smoothly in about 0.02 volt increments to a maximum reading of about 4.85 volts at WOT. Connect a voltmeter between pins A (usually dark blue) and B (usually black, or black/pink) of the TPS to measure TPS voltage.
neo71665
08-09-09, 09:22 AM
Yes do try to do a regular tune up first and foremost if its been awhile. This includes plugs, plugwires, oils change, fuel filter, and ect.



Was this problem there before the tranny rebuild? Are you getting a check engine light at all? On the Jasper motor, are you running your orginial throttle body and if so, has it ever been rebuilt?


I got a feeling your thinking the same thing I am, TV cable out of adjustment.
Boogieman
08-09-09, 02:29 PM
I took it for a good drive today.. I noticed an oil burning smell AND the Oil Pressure Guage was all the way up when accelerating and then the guage bounced down to 1/2 when I let off the gas.

Could it be the Oil Pump?
offroadfirstgen
08-09-09, 03:27 PM
ever think of a bigger motor? they tend to make things move along a lot faster


jk



i wouldnt think so but i guess it could...
Tink
08-09-09, 05:05 PM
Well, with a newer/rebuilt motor, you'll have higher oil pressure when you're on it due to tighter bearing clearances.... do you have a tach in it?

As far as the oil burning smell, 2.8Ls are notorious for leaking around the valve covers... both the 2.8L in our 83 S10 and the 3.1L in the Camaro leak around the valve covers and then the oil burns off.... literally, you could tighten the valve cover bolts once a month on those motors.
T Man
08-09-09, 11:15 PM
Fuel filter should be right behind the powersteering pump on the front, drivers side lower block. Sounds like a bad vacuum line to the map sensor. The fuel filter is a huge PITA in these. I ended up twisting off the hard line that runs from the filter to the TB. Make sure you use 2 wrenches, and get ready for bloody knuckles
Boogieman
08-21-09, 11:48 PM
I fixed it!! I gave it a tune up, nothing, so I changed the Fuel filter and the MAP sensor, and It was one or the other. My power is back....Thanks Guys, for all the input..
Tink
08-22-09, 08:41 AM
Always good to hear a problem is fixed!
pavegunner007
08-24-09, 10:52 PM
I took it for a good drive today.. I noticed an oil burning smell AND the Oil Pressure Guage was all the way up when accelerating and then the guage bounced down to 1/2 when I let off the gas.

Could it be the Oil Pump?

well i started a reply then realized the problem was fixed...
Blacklabel21
10-15-09, 06:07 PM
I got the same problem with my truck.I changed all that except the fuel filer that will be my next project.