gnomepunter

i have just recently put a 5.7 engine into my 88 that was in my 92 1500 i changed the computer and all to so but heres the problem.it wasnt accelerating right and had a skip or delay to it so i put a timing light on it and its timed perfect. but it still has the accel. delay when at low end but after it gets mid range in rpm it stops the delay and pulls amazingly no skip no nothing.i have checked all grounds on the engine.my friend says it could be my o2 sensor but im looking for a more informed person to maybe help me out as to any issue that might be causing this thank you in advance for any info

nauticstar87

Is the check engine light on?

gnomepunter

1 sec ill go crank and check

maxxman04

i suggest this only cause i've seen it before. is there any slack in the accel. cable? how does truck idle?

gnomepunter

nope its not on but my egr vac lines are not on but the engine ran for 2 years without those in my last truck so it cant be those

gnomepunter

my accelerator is solid no slack it idled bad till i timed it it idles great now.

maxxman04

sure could be those. egr runs on vacuum. if line not hooked up, you have a vacuum leak, which will cause hesitation during acceleration. and yes, motor will seem to run like a champ at higher speeds/rpm's with a vacuum leak.

gnomepunter

ok ill have to get some lines and hook that up to see if thats the issue noqw one more question lol the map sensor has 2 fittings on the back of it lol any idea which one or does anyone have a diagram lol i havent messed with the egr stuff for a few years and my memory aint great

maxxman04

i say get egr hooked up right. you did put the timing in "bypass" mode before putting timing light to it right?

gnomepunter

yea i bypassed with the wire on the harness