Yamaha+Toyota=Fun

Ever since I have owned my truck it has had sort of a rough idle. Lately it has seemed to have gotten worse. When sitting at a light my shifter shakes somewhat randomly. If I pump the brake or have the heater on high it will shake really bad. I also can hear it slightly miss if I put my foot on the gas and rev and hold it at almost any rpm. Also when driving the truck seems to buck around a bit when cruzing at 35-40+ mph. I have done all the tuneup stuff (plugs, wires, cap, rotor), I have checked and recheck for vaccum leaks. I just can't figure out what is going on. If I had a burnt valve would the truck have a rythmic miss, or would it be more random?

ekim121

My roommate has the same problem with his 22re, so I'm interested to see if anyone has any insight.

seaflea

It could be the injectors. the rubber seals that hold them in may need to be replaced.
the O-rings are not expensive or really hard to change. Its more time consuming than anything.

kryptik

My 94 pickup has been idling rough latly aswell. It only seems to happen when I slow down using the brakes

PirateFins

Well I had the same issues and it did turn out to be a bad valve. The oil seal for the valve was done and was letting oil down into the cyl.

Or something interesting that just happened. After rebuilding the head I still had somewhat of a rough idle. Well on my way to work on Tuesday I felt and thump and the truck studered. After that it ran fine and was as smooth as can be. Got to work popped the hood and saw that my AC belt was gone. So now I am wondering if the tensioner pulley or the AC pulley are going bad and was causing parasitic drag and making the truck run bad. I have also gained some (not much but every bit helps) gas milage as I have not put a new belt on. I might just leave it off since I never really use it.

Yamaha+Toyota=Fun

I have recently pulled off the injector and replaced the orings. I didn't replace the injector cap and the go into the intake, but I have sprayed them with Carb Cleaner and no chance in the idle at all. I dont think its a burnt vavle because I am not losing any oil, no smoke at all, and when I last checked my compression was fairly good. Could a leak in the exhaust somehwere in before the 02 sensor cause a lean condition, and a rough idle? If it makes a difference, right now I have the IACV port in the T.B. blocked off because it is not functioning correctly. Could that cause the idle to be rough and the it to miss?

Thanks for all your input,

Yamaha+Toyota=Fun

I seafoamed the truck yesterday, I didnt seem to help much. But I did notice something interesting. When the truck let it the huge cloud of seafoam smoke, I saw that there was also some smoke coming out of the joint in the exhaust where the manifold meets the pipe that goes the the cat. Could an exhuast leak right there cause a rough idle? Maybe this means i need a header......

4RocRunner92

I've had the same problem. Not with the brakes though. It sometimes will die unless I give it gad when it starts. It only does it sometimes. Could be a loose connection in there along with it?