Badkitty

I posted a thread describing what i thought was a transmission problem, but realized its the engine.

ok... This was a sneaky bug to find , but here goes. The engine is missing only at 2500-3000 rpm...It idles fine and runs fine above these rpms. Even reving the engine up either normally or a quick goose, but when you slowly raise the rpm up it starts missing and popping while maintaining 2500-3000. Rpm is just a guess by the sound as i dont have a tach, but i know approx the sound of rpm.

Which explains why the truck is jerking while only cruising with accelerator barely pushed down. I thought tranny was slipping or something.

So does anyone have an idea? i was thinking clogged injectors but wouldnt that miss in more of a rpm range?

84sr5yoty

"The engine is missing only at 2500-3000 rpm...It idles fine and runs fine above these rpms. Even revving the engine up either normally or a quick goose, but when you slowly raise the rpm up it starts missing and popping while maintaining 2500-3000. Rpm is just a guess by the sound as i don’t have a tach, but i know approx the sound of rpm."

These symptoms are really tricky to narrow down on the 22re. A lot of different things will cause those symptoms. Here is take on what to check from my experiences.

Misses and pops usually indicate either a lean mixture [vacuum leaks, plugged injectors(s)] or improper spark/timing (usually too far advanced).

First, pull codes from the computer.

http://www.4crawler.com/4x4/CheapTri...CheckConnector

Inspect every single vacuum hose for leaks. When I say inspect it, I mean pull every one of them off an inspect them, plug one end and suck on the other end to check for any leaks. Yes, it's time consuming and a pain in the ass.

Check the PCV valve. Clean it with carb. cleaner (or equivalent) and make sure it rattles when shook.

Check the rubber hoses and the plastic hose from the air flow meter to throttle body. Any leaks here will cause miss-fires, rough running or no running at all. Since your rig idles fine, this probably is not your problem, but it's worth checking.

Check the timing. Make sure you short the te1 connector and there MUST be a notable drop in the idle rpms (it should decrease slightly). If the idle doesn't change, you either have a bad connection on your short, or the TPS is out of adjustment. Timing should be at 5 degrees before top dead center with the te1 connector shorted at 750-900 rpms.

http://www.4crawler.com/4x4/CheapTri...CheckConnector

Speaking of the Throttle Position Sensor (TPS for short), check and adjust it. If it has never been touched, I guarantee you it will be out of adjustment. Go here for checking and adjusting the TPS.

http://www.4crawler.com/4x4/CheapTricks/TPS/index.shtml

Check the air flow meter. When these go out of spec, they cause all kinds of issues.

http://www.4crawler.com/4x4/CheapTricks/AFM/index.shtml

Oxygen Sensor (O2 for short): If you don't remember when the last time it has been replaced, or you haven't replaced it at all.....replace it. O2 sensors get lazy over time and send improper info to the computer. A faulty O2 sensor will give the EXACT symptoms that you're currently experiencing (miss-firing from 2000-3000 RPM's as well as poor fuel milage).

Perform a typical tune-up ie new spark plugs (NKG or Denso ONLY!!!), distributor cap and rotor, and new plug wires (NGK or genuine Toyota only).

Try these first and if they all check out correctly, I'll give you advice on where to send out the injectors for ultra sonic cleaning ect.

Badkitty

just a quick update..i havent done any of those checks yet..but just about 10mins ago i went to the 7-11 1/2 mile from me and when i started truck up and raise rpms slowly it did not miss, but when i came back 5mins later i did. So it wont do it cold. I dont know if this makes sovling problem any easier but i thought i should share that.

84sr5yoty

No miss when cold? That really sounds like the O2 sensor since it doesn't send any signals to the computer until the motor is at or near normal operating temp. Definitely start with a new O2 sensor, it'll probably cure the miss.

I usually get my O2 sensors from Kragen. Make sure you ask for a bosch O2 sensor with the connector (pull it out of the box to make sure before you pay for it). The other style sensors require splicing which you don't really want to do if you don't have to. The bosch sensors run around $45 dollars. Much cheaper than a genuine Toyota sensor which will run around or over $100.

Mostly Lurkin'

Sounds like what my 22re did in my 85 when the head gasket was leaking. It would idle ok, but when you give it some gas it started to miss real bad, until you get to about 30 mph...Good Luck...

BTW...I had to replace the head every time.

Badkitty

ok i havent had the time yet to take a look and try to fix engine. Today i started it up in the morning ( 50degrees ) idled for 2mins and left. No miss...got about 2miles down the road and there it is. Whats weird tho is i stopped 2times before destination and after the first stop the engine ran normal. I felt no miss or jerking. Stopped again rev'd engine and barely the slightest miss. When i got to destination, 5more miles, i sat and rev'd it up slowly, it missed like normal. Does this narrow it down more ? i plan on working on it tomorrow since i have it and weekend off.

I was also wondering how could the O2 sensor cause a miss ? I've had nothing but older hot rods , 69' and older, so i dont really know how some of this new smog crap works and effects other systems if they fail. Thanks again all for you help and info

phorunninduke

Are you sure it is a miss? It sounds like a TPS adjustment problem with the RPMs dropping consistantly at 3000rpm only after it warms up. I would say it is 80% chance that the TPS is bad or out of adjustment.

Tiger Paw

Also, check your plug wires. See if you're getting an arcing between them. My 22re started bucking and carrying on and gradually got worse. The wires looked fine but the insulation was wearing thin and they were arcing between the ignition coil wire and the posts on the coil. Was sure nice that it was as simple as replacing the wires with a new set.

Badkitty

um ya..ok...what is TPS ? Im having some trouble with my TPS reports. lol any know what movie thats from.

84sr5yoty

Is it office space? Can't remember.

TPS testing and adjusting proceedures

http://www.4crawler.com/4x4/CheapTricks/TPS/index.shtml

Jeff91

84sr5yoty,
I am having similar symtoms with my 91 22re pickup. I did a search and found your reply. I am going to do your recommended checks.


Just wanted to say thanks.
Jeff

Badkitty

let me know what you find jeff, i have no yet gotten a chance to work on truck..damn work.

84sr5yoty

No problem, glad to help. Hollar if you need anymore advice.