Engine surging

ALAG321 · 09-11-2008, 04:26 AM

I have a 2002 W22 chassis with 30,000 miles. On my last trip, I notices the engine "bucking" or "surging", especially during acceleration. First, I was thinking plugs, wires, etc., but I don't hear a miss in the engine. Maybe fuel filter? Has anyone else had similar problem or have any ideas?

ALAG321 · 09-11-2008, 04:26 AM

I have a 2002 W22 chassis with 30,000 miles. On my last trip, I notices the engine "bucking" or "surging", especially during acceleration. First, I was thinking plugs, wires, etc., but I don't hear a miss in the engine. Maybe fuel filter? Has anyone else had similar problem or have any ideas?

TAN · 09-11-2008, 04:33 AM

When mine did that (surging) It was the fuel pump. Cost me $1204.00 to have it replaced. First I changed the fuel filter this was not neccesary as it turns out. Cost $75.00 then I changed the air filter ($20.00) this made no improvment. It ran like a charm after the $1204.00 fuel pump instulation.

max49 · 09-11-2008, 05:07 AM

Before you go after the fuel filter/ pump, do not rule out a plug wire.
Mine seemed like it ran fine when it was not under a load but when accelerrating or going uphill; the best way I can describe it is ; it felt like I was pulling a large 1/2 full tank of water. It felt like the water was sloshing backwards , apparently when the engine tried to fire on the bad plug wire. Mine was the plug wire closest to the drivers feet.
It seemed fine when the engine was'nt on a heavy load. Your description as 'surging' sounds almost classic for a bad plug wire. Let us know what it turns out to be.

At a different time, I did get the 'check engine' light but it seemed to be running fine for about 2000 mi until I got it to the WH svc cntr checked the code and replaced the fuel pump, or at least they said they did, under warranty. Mine was running good at the time, except the check engine light so I would have been very skeptical if I had to pay for it.

Rick Long · 09-11-2008, 05:52 AM

Don't rule out BAD GAS... Many have reported similar problems and it turned out to be bad gas.

edgray · 09-11-2008, 06:17 AM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Maybe fuel filter? </div></BLOCKQUOTE>
ALAG321: That would be my guess. It is also the cheapest and easiest place to start. Yours is located just in front of the rear axle in the driver's side frame rail. It should cost less than 10 bucks and you need a AC Delco GF481 or equivilent. Once the new filter is tight, a test drive should prove if that, or something else, was the problem. GOod luck. ED

RVThere · 09-11-2008, 08:17 AM

It may be a long shot but was it raining or the road wet when you have bucking problems?

My 2003 WH Suncruiser would miss when it was raining outside. Seems a lot of water comes off the windshield and runs right into the top gap of the engine hood. That rain water would get into the air filter and impede the airflow resulting in the miss and then surge. Once I put some foam weatherstripping in that gap, the problem stopped.

Duner · 09-12-2008, 07:16 AM

I'm with max49 on this and will bet the plug wires are burnt.

I've had the plug wires burn twice and there always was a surging when accelerating. WH service validated the problem when they read the codes. The code reader told them which cylinders had the problem. You won't feel/hear a miss because the wire is still passing some spark....the wire is burnt and has increased resistance so the engine doesn't miss like a fouled plug or if the wire was off the plug.

WH put the Vent Kit on mine under warranty. The same month I had Ultrapower installed. I've put another 20,000 on the rig with no more burnt wires. She runs smooth as a baby's bottom.

At 37' with 3 slides, your rig is like mine weighted down to max GVWR, so that engine is really working hard. The UP would make a big difference.

Be sure to get back and post to this topic to let us know what did fix your problem.

Good luck,

TAN · 09-13-2008, 05:33 AM

After reading MAX49, I started thinking (somthing I should never do my DW says)The fuel pump was changed then it was test drove and was still runing badly so then the plug wires were changed. So did I need the fuel pump or just the wires. I guess I will never no.

DriVer · 09-14-2008, 05:28 PM

I hate to assume that anyone would just throw parts at a problem without fully running diagnostics using a Tech II instrument. A T2 will normally detect a bad fuel pump.

TAN · 09-16-2008, 05:27 AM

Thanks DriVer I feel somwhat better now I too don't think my fuel pump would of been replaced unneccesarliy.

ALAG321 · 11-06-2008, 12:34 PM

Alright, sorry about the delay in the fix, but I have been too busy to work on it. Today, I replaced the plugs and wires and it runs like a charm! I almost could not believe how smooth it runs now. Guess it has been a problem for a while....Hope this helps someone else with this problem.

Capt Joe · 11-06-2008, 04:45 PM

I had the same problem last month and mine proved to be the coil on the #6 cylinder. Put a scope on it that showed #6 misfiring. The wire looked/tested fine and the plug was wet. New coil and all was FINE.
Just goes to show that similar problems/symptoms can have different causes. A GOOD shop and one that will think through a problem instead of just throwing parts at it sure pays big dividends.

Full-Timers · 11-06-2008, 04:45 PM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by DriVer:
I hate to assume that anyone would just throw parts at a problem without fully running diagnostics using a Tech II instrument. A T2 will normally detect a bad fuel pump.

</div></BLOCKQUOTE>Yes but will it detect a plugged pickup screen on the fuel pump?