popping noise when accelerating

[thebeastjuggalo]

on my way back from my trip, the flex pipe i had in place of my cat converter (wich was removed before i got the truck) came off and i couldnt get it back on because it was too hot and i was about 65 miles from my home. so i drove it the rest of the way there, but after going like 40 miles on the freeway with the flexpipe off i started hearing a poping when i got up to or above 2500 rpm (it popped slightly at lower rpm's) and even after welding in straight pipe in place of the flex it still pops. could i have sucked a gasket or somthing? i have never run into somthing like this. and i dont seem to be suffering any performance losses or anything, just kinda unnerving having it pop like that.

and it also does it when i give it gas wile idleing

'95 jimmy 4dr 4x4

[Chris Stewart]

Is the Check Engine light on?

[DelCoch]

Maybe you have an exhaust leak where you did the welding??

[thebeastjuggalo]

there is no check engine soon light on, only very small leak in weld on exhaust almost dont notice it.

someone i work with said to check the plugs because it also sounded like i had a miss, so i checked them before i had to go to work today and one of them was slightly loose, so cold air was getting in there and messing things up, i tightened it down real quick and went to work, tommorrow im going to check the rest of them because the popping is still there just not nearly as bad as it was.

also the person said that with the plug being loose it could have burned a valve or somthing like that, and he says its not a cheap thing to fix at all.

[thebeastjuggalo]

i put on a whole new exhaust system (magnaflow cat, flowmaster 40, pipes and tip, all welded on by professional) and the popping is still there, i took it to machanic and he hooked it up to the diagnostics thing and it said i was running lean, so he checked for vaccume leaks and there was none, checked fuel pressure on port by engine, pressure was fine there, so the only other thing he said could be wrong is the fuel rail spider thing inside wich isnt cheap to fix, he said it sounded like it was missing on 2 cylinders....anyone else got any ideas? and yes the check engine soon light comes on when im on freeway only.


it also pops wile idling, not just when accelerating

[riptide44]

1st check the o2 sensor - it will almost never show a code until the dire end - if thats ok im pretty sure you have an injector issue as in a sticking one - which means replacing the fuel injector spider that you mentioned

i had to do mine recently and tried an aftermarket rebuilt unit - 1st one failed 2nd one gave out 2 days later but it took me a week to figure out that the second had failed and it showed all the sighns you have - pressure looks good , no bleed down , but a popping on light acceleration and lean misfire at cruising -

before digging into the expense though - did you have the fuel volume checked as in running the bleeder line off the fuel tester into a jar . its worth a look even though these injection units fail more than regulary .

[thebeastjuggalo]

o2 is the one on the intake or exhaust? and how do u "check it"?

[hotrod_chevyz]

Probably burned a valve due to the exhaust leak.

[riptide44]

yes the o2 is on the exhaust pipe - scanner is the best way you want to see how fast the numbers crossover/under the 500 mark should be rapid changes not slow - if its stuck dead lean or dead rich its dead -LOL - but either condition would have alot worse driveability issues - you can use a dvm on the signal wire - not the 5 volt wire and watch the changes go above and below .500 mv or if you have at least 50,000km on that sensor it should be changed out anyway - alot of people dont consider it a maintenance item but it realy is - they slow down over time --- i'm still thinking its going to wind up at the fuel injection spider though .