ryan954

I have a 1995 Toyota Tacoma with a manual transmission with a Jasper Rebuilt 22RE engine. The truck has about 144,000 on it, the engine about 50,000. The truck has been loping for about a year now, but it is starting to bother me. When you start the truck, it will start a smooth idle around 2,000RPM and work up to about 2,500RPM, after a couple of minutes it will begin to lope. When in neutral, the truck will lope between 1,800 and 2,000 RPM. If the brake is applied, it will drop down to loping between 1,000 and 1,200 RPM. While in gear/moving, the truck does not lope, but will only maintain a smooth coast with the throttle depressed at least some. If I attempt to let the truck idle along in any of the gears, it will coast along smooth for a couple of seconds and then the idle will suddenly drop and the truck will lurch, at which point, I will tap the throttle and it will lurch back into coast. I did some research on this throughout the year, but everyone's symptoms seem to differ. I tried to adjust the idle, but the idle adjustment screw does pretty much nothing; i can screw the idle adjustment screw all the way in and the truck still runs as usual. I took it to my local shop about a year ago, they called me to pick up the truck. It worked great for about 15 minutes, but upon pulling into the driveway it began to lope again. They said they found a vacuum leak at the throttle body, so I pulled the throttle body and resealed it with gasket maker thinking on the 15 minute trip home, something they had done had blown-out, but it did not solve anything. It has loped ever since then. They said it needs a new throttle body, but I want to make sure it is actually the throttle body; according to my research it can be a ton of different things. Thank you in advance for your assistance!

xxxtreme22r

Idle is too high. with brakes applied it will cause a fuel cut to happen. Like a rev limiter. Now you just got to figure out why the idle is high. Could be a vacuum leak, timing too advanced, misadjusted throttle position sensor or several other things. High idles are a rather common issue on here and tons of info on it.

BTW, if it has the 22re, it's not a Tacoma, it's just a pickup.

abecedarian

So, it's a '95 Tacoma with a 22re? Are you sure?
Tacoma's (from 94.5 up) had 2r/3r 4cyl engines or 5VZE V6's.
'95 "Pickup / HiLux" had the 22RE 4cyl and 3V v6.
T100 only had the 3VZE- pre 95, or 5VZE 95 up, and 3RZ 4cyl offered

Anyhow, yeah. If you really have a 22re, the idle's too high. The 22re ECU will cut fuel whenever you press the brakes and the idle's about 1000 or so. Obvious things to check are the throttle position sensor, idle air adjust screw, auxillary air valve and the duct to the air flow meter, as well as any other menial vacuum leaks such as to the brake servo or PCV system.

ryan954

Yes, it is a 22RE. It is a pain purchasing parts from an auto store for the truck, because engine parts do not pull up correctly under a 1995 Toyota Tacoma; I have to use a 1994 Pickup. It is titled as a 1995 Toyota Tacoma though.

monti248

my truck had the same problem. replaced the TPS and fixed it.

pruney81

I'm pretty sure like Abe said if it has the 22RE it's just a 95 Toyota Truck....

wyoming9

iTrader: (1)

It has to be a typo on the title. This could cause you issues if you go to sell this truck!!

Have the vacuum hoses been replaced by now they are going to be brittle. A bad hose or any extra air being drawn into the intake can cause this.

Vacuum hose on the wrong port will also cause this.

Is the shaft on the throttle body wore to the point it is sucking air that could be why they said you need a new one. Has it been cleaned real good???

scuba

No such thing as a Tacoma with a 22RE. A "95" Tacoma will show "1995.5 Tacoma" on the title. Go to DMV and straighten that out.

Still want to call it a Tacoma, post pictures and we'll confirm that it's not a Tacoma.

xxxtreme22r

22re were NEVER in a Tacoma. Not factory anyway. ANd I have NEVER seen anyone swap a 22re into a Tacoma. No such thing as a 95 Tacoma anyway. As Scuba sad they are 95.5 Tacomas. Some autoparts stores are stupid, they don't know the difference between a 95 Pickup and a 95.5 Tacoma. And if your DMV says it's a 95, then they are also wrong.

ryan954

Alright, update, pulled the throttle body. Pulled the ACV off and cleaned it really well. Cleaned the throttle body. Replaced the TPS, marking where the old one was situated. Still loping. I am going to return the replacement TPS and try replacing the ACV valve. Any comments? Thank you in advance!

xxxtreme22r

What are you doing to test these things before replacing them? Have you attempted to lower the idle, check your timing, simply re-adjust the TPS to proper specs before throwing parts at it?

Remember check doesn't mean take old part out and replace it.

ryan954

Another update...this is crazy...so, like I said in the last post, put a new TPS on it and it continued to lope. (To answer the following post: I was testing the original TPS using an OHM meter. The values the original TPS were producing were all over the place. I had the OHM meter set at 2K; however, when I tested the new TPS it seemed to test correctly. Also, the idle screw was all the way in before.) So, not wanting to replace a functioning TPS, went back to original TPS and fired the truck up with the idle screw all the way in. The truck is not loping. It is still idling too high; around 1050-1100 RPM, when warm; however, it is not lurching when driving and is not loping at lights with the foot on or off the brake. Any comments? Thank you for all your assistance!

xxxtreme22r

Start checking for vacuum leaks and miss routed vacuum lines as stated above. Also check your ignition timing. Making sure your properly using the jumper. This will eliminate the possibility of too far advanced timing causing a high idle.

You also setting the TPS properly via the meter not just throwing it on there correct? No CEL's correct?

Another trick I like to use is to pull the PCV valve and block off the vacuum hose to it. See if idle changes. This will tell you if you have a vacuum leak in either the oil pan, valve cover or timing cover. Places where people generally don't think a vacuum leak can happen.

A similar thing to do is pull the brake booster vacuum line and plug that too. That can also be a hidden source of a vacuum leak. You would generally see this if the brakes aren't working like they should though. But it wouldn't hurt to eliminate it.

ryan954

Another update...drove to the gym this afternoon...drove great the whole way...upon arriving and the truck warming up completely...the truck was actually dropping to about 500 RPM at stops and shuddering...opened the hood and turned the idle adjustment screw out about 1/4 turns and it now idles at 750 RPM. Everything seems to be fine. I am not very experienced when it comes to working on vehicles, but I love to learn. How do I check the ignition timing / jumper? Regarding the TPS, with a pencil, I marked where it was before taking it off the truck, so how do I set it with the meter? Thank you in advance!

xxxtreme22r

Ignition timing procedure: http://www.ncttora.com/fsm/1993/ignition/5distribu.pdf
NOTE: With jumper in CEL must be flashing. If it's not flashing then Jumper isn't making proper contact.

TPS adjustment procedure: http://www.ncttora.com/fsm/1993/engine/34throttle.pdf

BMcEL

.....

ryan954

Update...have been running the truck now for two whole days...had to adjust the idle a couple of times during the first couple of trips...now idle screw is about 1 whole turn out...truck has been running perfectly all of today...idling at 750RPM, smooth acceleration and de-acceleration, and no loping...every now and then, very infrequently, the idle will drop to 500RPM coming to a stop but a slight tap of the throttle quickly brings the idle back up to 750RPM...Thank you for all of your assistance!