Inconsistent hesitation and lunging (UPDATE: problem fixed?)
Posted: Sun Jul 27, 2008 9:52 am
I decided to take a little road trip today into Wisconsin. It was a back roads trip where my speed stayed between 30-55mph without any problems. About two hours into the trip I decided to start heading back. About 30 minutes into the return trip I slowed down for a corner. Once around the corner I was doing about 30mph so I shifted into third gear. I accelerated to about 35 mph and then it started hesitating , bucking and lunging forward. The best I can describe it was like something was rapidly cutting the fuel on and off. I thought it was going to stall. This lasted for a couple seconds as I tried to accelerate and then I took my foot off the gas. I pulled it into neutral and coasted down to about 30mph. I put it back into third and accelerated. No hesitation this time and I was able to get back up to about 55mph.
All was well for about 20 minutes and then it happened again. I was accelerating and shifted to third at 30mph. Once I reached about 35mph it shuttered and lunged for a couple seconds until I let up on the gas pedal. A few seconds later I was able to accelerate past 35mph without any problems.
I changed my route so I could stay on roads between 45mph-55mph. At one point I may have felt a slight hesitation at 45mph after shifting into fourth gear, but I’m not sure. I believe I went another 20-30 minutes without any problems. I’m getting close to home by this point. At a stop light I go through the gears and now it happens again in second gear at 25mph. It hesitates and lunges forward hard enough to shake me. I continue accelerating and shifted into third. The bus continued to hesitate until I was over 35mph and then it mellowed out and operated like normal. I was able to make it home without it happening again.
To summarize, the hesitation and lunging occurred three times. Twice in third gear at about 35mph and once in second and third gear between 25-35mph. It didn’t happen at lower speeds in first gear and I don’t think it happened at higher speeds in fourth gear. The entire trip lasted about four hours and I spent most of the trip running between second, third and fourth gears with my speed ranging between 30-55mph.
My instinct tells me to change the fuel filter in case it’s clogged, but that’s just a guess. I’m not sure how the bus would act with a clogged fuel filter but I would expect the problem to be a little more consistent then I experienced.
Does anyone have any suggestions?
All was well for about 20 minutes and then it happened again. I was accelerating and shifted to third at 30mph. Once I reached about 35mph it shuttered and lunged for a couple seconds until I let up on the gas pedal. A few seconds later I was able to accelerate past 35mph without any problems.
I changed my route so I could stay on roads between 45mph-55mph. At one point I may have felt a slight hesitation at 45mph after shifting into fourth gear, but I’m not sure. I believe I went another 20-30 minutes without any problems. I’m getting close to home by this point. At a stop light I go through the gears and now it happens again in second gear at 25mph. It hesitates and lunges forward hard enough to shake me. I continue accelerating and shifted into third. The bus continued to hesitate until I was over 35mph and then it mellowed out and operated like normal. I was able to make it home without it happening again.
To summarize, the hesitation and lunging occurred three times. Twice in third gear at about 35mph and once in second and third gear between 25-35mph. It didn’t happen at lower speeds in first gear and I don’t think it happened at higher speeds in fourth gear. The entire trip lasted about four hours and I spent most of the trip running between second, third and fourth gears with my speed ranging between 30-55mph.
My instinct tells me to change the fuel filter in case it’s clogged, but that’s just a guess. I’m not sure how the bus would act with a clogged fuel filter but I would expect the problem to be a little more consistent then I experienced.
Does anyone have any suggestions?