Occisionally misfire while motor not under heavy strain

they shifted the load by pulling ..can not work any more out

My personal suggestion would be to go for these repair catalogs. I know this website www.reliable-store.com that i used to buy them from, and they sold online it was very good manual. Go ahead, I bet.

The plug wires on this model year and prone to burn through, replace them all, do one at a time and always put them back in the factory wire looms they run through, that is very important, replace any you may break. Use high qyuailty oplug wuires foractory parts are preferred..

This can be an elusive problem to find. You may have the problem with no load and it just does not show up. You have to look at the difference it makes on the truck to carry a load.

A soft spot on a tire would make more of a difference with a load than without. Front-end play can manifest itself when the weight shifts off the front-end and allows the parts to contract and form excess play. This would correct when braking allows the weight to shift back forward.

Play in U-joints. The excess weight would strain worn needle bearings in worn U-joints because there is more torque required to twist the driveshaft with a heavy load.

Bad motor mounts or transmission mounts. If weak, would allow drivetrain to pitch.

Transmission settings. If automatic, could be needing an adjustment for shift points.

Bad wires, cracked sparkplugs if a gasoline motor. Cracked coil-pak

If you are under the Mileage Warranty, this could be a Warranty problem.

The SES light flashing means the engine management software has detected a misfire condition resulting in exceeding 3 times the federal limit of emissions. Under heavy load such as acceleration one or more cylinders are misfiring and once cruising speed is reached the engine is under a lighter load (10 to 20 percent ) that is why it stops flashing several causes of misfires are worn spark plugs ,spark plug wires, faulty ignition coil or coils fuel injector or fuel pressure problems a quick check of the computer to retrieve trouble codes should identify the problem cylinder or cylinders and will direct you in the right direction to find the faulty component but will not tell you exactly what is wrong certain test must be performed to isolate the cause.

pull wire off # 2 see if idle changes if not there s no spark... test coil....test all vacuum lines for leaks also. if all good then idle speed sensor.

Hello Jhz.
When in overdrive the engine is under a lot of strain. Combine this with lean fuel mixtures in vehicles today and that is when you need the most spark.
So what I am getting at is that you are experiencing misfire.
This could be caused by a lean fuel injector, poor spark plugs, bad ignition wires or a bad ignition coil.

try a new catylatic converter,If it only goes 55 m.p.h , or under heavy strain,thats usully what it is.

Most likely its the motor under the seat. if u have to replace the motor thats gonna be expensive (couple hundred), but if u can here the motor its probably straining which you will have to get a new one or try what i do. My motor doesnt work well going forward so it would just sit there and strain, but i let it strain as i somewhat forcefully slide forward as if ur trying to hump ur steering column but while still staying on the seat.

hello before you replace parts you might not need try to test the map sensor see if it is within range this works with vacuum changes in motor goodluck please rate