So does it still start hard and run bad for 10 sec's? Bad O2's and low temp stat wont help this. Have you pulled the Vac line off the fuel pressure reg to see if it is leaking fuel into the manifold? I'm a small independant shop and have replaced a bunch of these?
John

 

Ok. Well I'm thinking I could just put my stock stat back in and once I go to have it retuned put the 160 stat back in before I go to the tuner. And I might modify my exhaust a little to maybe raise my EGT's a little if they're too low.

 

Yes it does that but still idles funny regardless, hesitates, skips and back fires whenever under a load, and the engine seems to skip a little while crusing down the highway. He never checked the fuel pressure but I could do that as well. Whats the best way to go about checking that? Also, he did a vacum and compression check and said everything was ok.

 

The issues I've had have been leaking. When they do go bad they leak into vac line. So it bleeds the fuel rail down and dumps the fuel into the intake. It causes hard start, stall if not enough gas is given and poor running until the motor burns up all the extra fuel. About 10 sec. Also it causes a black puff of smoke out at start. The easy test is to take off the vac line off at the reg after the trucks sits for 10-15 min or longer. If there is fuel in the line its no good.

John

 

Ok. Appreciate the advice, I'll be sure and do that sometime tomorrow once I get home from work and get a chance to fix my truck. Where exactly is the vacum line located on the intake manifold. I'm not to familiar with fuel lines other than the furl rails themselves. I try to stear clear of it if at all possible. he he he

 

Red I just happen to have a surburban sitting in my shop for one. Its on the left side of the motor above just above the coil pack. There is white connector and the reg is just above it. It has a single vac line going to it. Very simple to check. Shut truck off and remove the line. After sitting a bit if fuel comes out its leaking.

John