sk3.0

Hello all, got a problem.(imagine that) Its kinda a long saga so I'll try and get to the point. I ran a search but went into info overload.

90 3.0 pickup 5spd, just over a hundred thousand miles. Owned alittle over a yr. (Wish I never sold my old 22re....)

Part1...

I live at 10000ft in a Co. resort town so I drive up and down mountain roads all day. This truck is used for work and play, I maintain it well but drive it hard(its a yota!) 30 t0 60 mile a day of stop and go mnt. driveing.

So 6 months ago I replaced the batt and the idle went from rock solid 700rpm to all over the place. Truck would almost die after a couple minute climb when stopped. While driveing it runs great, now power loss or hesitation. Fuel economy seemed fine aswell.

Long story short had the truck looked at by the way to exspensive local shop and they said it was the cat. It did have that rotten egg smell so I said OK. Kinda fixed the problem but after I rallyed up to the Eisinhower tunnel 15/20 or so mile at 4500 rpm in third the idle retuned to being rock solid. Problem solved or so I thought............

Part2.....

Ok, alittle over aweek ago I cleaned the batt terminals. Hooked back up and low and behold the ghost in the machine is back., grrr. Idles all over the place and now it will sputter out and die if I let it after a hard climb. Still drives great but when its stopped its not happy. Shortly after check engine light came on, I jumped the diagnostics box and pulled 21, o2 sensor. Replaced o2 and pcv valve(great location for pcv). No improvement.

Checked for vacum leaks, none to be found. Plugs and wires seem ok, all electric conections have been cleaned. Checked MAF sensor conections, looked good. What do you guys think? bad MAF, EGR, Timeing, ECU(NOOOO!). So many thing it could be.....

I made an appointment with a yota dealer in Denver to find out whats going on...their cheaper than the local shops if you beleive that. Please throw any ideas you have out here, would like to just not start throwing parts at it.

Anyway thanks for any info and I'll post the yota fix next week if it gos to the dealer, help someone else out maybe with the fix.


Sean....

Bumpin' Yota

how much does the idle actually vary? (rpm high to low)

Could be the TPS...

sk3.0

Thanks for the fast response! from 50/100 rpm to 1200 rpm. It surges when stopped, its all over the board. I just whipped it around town, 50degres and raining and idle held alittle better500/700 rpm. Allthough I just turned off/on the engine and it did the same up to 1200rpm the diveing to almost nothing. Back up to 400rpm then back down to nada, up down up for a minute then settled at 500rpm. Weird stuff...think its in the tps realm? Maybe some sort a temp sensor is screwy? Thanks for any help!

sk3.0

Thanks for the responses guys, rainy and dark out. I'll check the above mentioned items in the am. Thanks again.

TNRabbit

It appears to be aggravated by disconnecting the battery, so I think is would be prudent to start with what might be affected when you remove power & reconnect....I can't think of anything in particular, unless you just have a short somewhere. Didn't you say you got a O2 sensor code at one time? Is the wire to the O2 sensor bad? are the connections to TPS & ECU OK? Check your distributor for a good connection & any obviously worn or broken parts....

Is the dist. cap cracked? Just throwing possibilities out here....

Bumpin' Yota

Another idea is to check out the VAFM (what you called the maf) it should have a specific output across the various poles for various position of the flapper. But honestly I think your TPS (throttle position sensor) is on the way out....

Propayne

i know this might sound stupid, but mine was havin an idle problem....check your throttle cable on top of your engine where it goes into the throttlebody(?) and there may be some dirt/crud built up in there like there was mine.

mine used to idle all over the board as well, got that cleared out and it stays at 7-800

sk3.0

So had a day off with nothing to do so I tinkered around with the 3.slow. Checked throttle cable, replaced rotor, cap, sp. wires, plugs, oil change, 02 sensor, and going to throw a new fuel filter in it in the next day or two. As expected the idle issue is still their, but man I thought it was running well before (other than idle) the old 3.0 is running great! MPG is way up and the engine is super smooth. Went wheelin in 4 low for an hour, drove around town and took it on the highway, like a new truck.

Back to the idle. As BumpinYota stated, its looking more like an TPS issue. Upon researching it looks like a complicated procedure to install/calibrate the TPS unit. Don't feel confident in my abilities as far as replaceing it. Still might be going to the shop.

Any other Ideas? I'll let you know what the fix is when I find it.

sk3.0

Up and running great!!!! After a few hours at a stealership the tech checked the TPS, EGR ect( all good) and found a rip in the back of the main air intake tube. Replaced and no more idle issues. I'm kicking myself for overlooking this, guess I should of triple checked.

The bad.....giveing the dealer coin.

The good.....was way cheaper than expected, was thinking alot more coin would be needed.

The great.....had enough Yota dough left to have a 2.25" catback with a delta 40 installed. The CB with the already installed KN induction realy lets my truck breath better at 10000 ft. Sound pretty good to, no tip on the exhaust. I figured it would just end up getting ripped off.

Great sight! Thanks for support/trouble shooting even though it was my fault for overlooking such a simple fix. Such is life.....time to get some gas 270mls (town and about 150 hwy) and the fuel light is still not on! or its burnt out.