I have a 1993 yukon.

Comming off a stop light and giving it gas it goes into a stall, i have to gas it up to keep it going. The tachometer is jumping erraticly up/down like its shorting out, The trany shifts late and hard due to this problem and i'm having lack of power. I got the check engine light to blink a code 44 due to the idle diving into a stall, so i don't think its that valid....I just made it home and now all it does is crank with out starting.

Any ideas guys?

BTW...two weeks ago i did the control module (greased it) and coil.

A few days ago i saw the tach jumpimg once it hit 3,000 up/down about 500 rpm.....the engine was running perfect....it looked like the tach was shorting out when it hit 3,000 for a second than normal.

-john-

Code 44 is for a lean exhaust indication.
I would begin with some basic diagnostics for the no start problem...does it have fuel? spark?
Pull off a plug wire and remove the air cleaner assembly...have someone spin over the engine...does fuel spray from the injector?
does spark jump out of the plug wire?
Let us know what you find

Code 44 is for a lean exhaust indication.
I would begin with some basic diagnostics for the no start problem...does it have fuel? spark?
Pull off a plug wire and remove the air cleaner assembly...have someone spin over the engine...does fuel spray from the injector?
does spark jump out of the plug wire?
Let us know what you find



Thanks for the quick reply......

I sprayed carb cleaner down the throttle body.....and she started right up and then died. I changed the fuel pump relay and it did nothing.

I now beleave it is the fuel pump, especialy since i can't hear the pump activate with the key in the on position. I will probably have it towed to a shop.