99 just running rough

99 4Runner with183k. Had it for about 2 years. Overall has been running well. I took on the job of plugs and wires today and with the help this forum all worked out well. I was hoping it would cure my rough ride. Idles smooth. Over 30 mph just seems “not smooth at all”.

Valve cover gaskets and full exhaust was done last year.

Any suggestions. No codes. No stalling. Not sure what to look at next. I was thinking the fuel filter and will probably take this task on soon as well. Might be original.

 

If I can clarify a little….while accelerating at about 30-40mph gets louder, lots of vibrating from the engine…..stops immediately if I let up on the gas.

 

Any codes displayed? Remember to clear out the old codes (if any), then running it to look for new codes. Even if it doesn't display a code (or the CE light) when the problem isn't actively happening, it will remember any codes set. You can read them out easily with a commercially available code reader.
Any codes might give you a decent starting point for your trouble shooting.

Good Luck!
Pat☺

 

No codes at all. Nothing to clear. I figured new plugs and wires may address the issues. Unfortunately still happens.

I am going to attempt to clean the MAF…….although no codes are directing me to do so, I’m thinking just leave it alone???

 

there are a couple of pages of this discussion . . . several times the solution was to replace a fuel injector, which didn't code. i'm just starting to get to mine, which codes miss on cyl 3. my plan is to look at all the spark plugs first, 'cause they can talk about it.... then replace the coils and wires. after that i plan to replace the fuel injectors and look for vacuum leaks while i'm doing that. then, after that . . . . . .

 

FIX IT. the problem I assumed was the torque converter. Turns out it was driveshaft universal joint. 200.00. I’m good.

 

Glad you got it fixed! Thanks for letting us know what you found.

The u-joints on my 99 are still factory, but I lube them twice a year, spring and fall. AND if I go through any significant water puddles. I try to keep the good and greased. It seems to make a difference.
Before I sold my 87 4Runner, it still had it's factory u-joints on it. Once again, I kept them full of grease. Sure seemed to work well...

Now, go out and have fun!
Pat☺

 

Yes you are correct. There was a lack of maintenance over the yrs for sure.