View Full Version : start>hesitate>pop, pop,pop

Walt Stanley
July 3rd, 2006, 14:34
HI: '98 6 124,000mi. It goes like this, I start up the truck, I start to move, it hesitates and I hear a pop,pop,pop, like a back fire in a carburetor, catches and off I go like normal. (I know I have fuel injection). I'm thinking: O2 sensors or MAP sensor.

July 3rd, 2006, 14:56
Does this happen all the time, or just right after a cold start? Check the Coolant Temp sensor in the Tstat housing. If it happens all the time when starting from a stop, check the TPS. O2 and MAP sensors would probably not cause your symptoms.

Check the timing as well, bring #1 to TDC and check the distributor's position. Timing chain could have jumped.

Walt Stanley
July 3rd, 2006, 15:15
Ahh! It only happened twice so far. If I can remember, it was with a hot start and a few days apart.
I've tried reading a lot of posts, but they seem to end before a definite answer is found.

August 1st, 2006, 17:28
My 93 does it every time on cold start... haven't done any diagnosis yet, but if I find what it is, I'll let you know what fixed mine (I'm sure your 98 won't be the same as mine, but info is info...)

Walt Stanley
August 1st, 2006, 20:05
Thanks. I'm thinking, fuel pump, clogged injectors, O2 sensor. It used to start on the first turn of the key, but now I may have to try twice in the AM.