Hank the Tank

I own a 99 toyota 4runner 2WD automatic with 200,000 miles. The truck wasn't accelerating good so I changed the spark plugs and wires, no luck. Then the gas filter, no luck. Used 3 bottles of injector cleaner with 3 tanks of gas, no luck. So I'm wondering if it could still be dirty injectors and what I should do? Can I take it to a shop and just have them do the fuel system cleaning for around $80.00 or is this just a waste of money. Could it be possible that I need new injectors? I'm running out of ideas to get this truck running good again. Does anyone have any ideas? What would you do?

socal_99

Is it idleing rough or just low?

Accelerating sluggishly- are you able to reach highway speeds?

Try looking at your catalytic converter next time you go for a spin- is it glowing?

I had an issue where the vehicle would not run properly- I changed plugs and wires- no difference. Car wouldn't run past 45mph. Cat was running cherry red.

Replaced the coil which fixed the cause but by then, the cat was toast. Had to replace it as well- finally, success.

Hank the Tank

Thanks for the response! The truck will idle rough and sometimes when sitting at a light it will sound like its gonna stall but doesn't. It's funny that you asked me about the cat because I was wondering if it could be something with the exhaust system because it has a very strong/odd smell coming from it. I will reach highway speeds fine just not accelerating like it should. Could it still be the cat? Is that the only way to tell if its bad is if its glowing red? Thanks Don

socal_99

No worries; I had a similar problem so I know how frustrating it can be trying to figure out a problem like this.

Remember that the cat will be the 'victim' of some other problem.

I too, could smell a weird 'hot' smell when stopped and the vehicle would idle kind of slow/ erratic. Under full acceleration, you might even hear a noise which will sound like an exhaust leak- except it will be your egr valve. The backpressure form the exhaust will be strong enough to cause exhaust gas to flow backwards and vent into the engine bay.

All of this was caused by a failing ignition coil. The coil wasn't sending a strong enough spark to whatever cyliner so unburned gas is being ignited when it gets to the cats which will cause them to glow red, even at idle resulting in massive backpressure.

Oh- and when my coil was bad, my mileage dropped significantly- by 10mpg. And after replacing the coils idle was ok but symptoms persisted because I had toasted my cat. Clogged cat will allow you to idle ok but the telltale symptom will be a very noticeable drop in performance. In neutral, the engine was unable to rev past 3500 rpm! It sounded like a pressure cooker when trying to accelerate.

Although it sucked having to replace the cat, I did end up replacing the coils, plugs and wires and with 160k on the clock, this is cheap insurance for (hopefully) another 160k of trouble free service.

quietman187

Go to autozone and get some MAF cleaner and soak yours, its often over looked and gets very filthy. Its delicate so be careful no to blast it too hard with the cleaner.

Hank the Tank

Sorry this may sound stupid but what are people referring to with MAP?

Hank the Tank

Air filter?

quietman187

Mass Air Flow sensor. Its just after your air filter on the way to the intake, it has a harness connected to it. Its easy to take out and clean, do a search, sure someone has done a write up already.

wii_tarded

Ok, I have low idle, a new cat, and no acceleration problems. I have to tap the gas to rev it up a little to let the clutch out so I can take off...but then I can run pretty hard. It just idles around 250 rpm after it warms up.

Oh, this is on my '91/'96 swap. The 2000 runs great.

rmc88

So, one, I'm new to this forum. Second, my 91 runner is having a similar issue with acceleration and lower than normal idle around 100-400RPM which the bottom end of that should stall the motor. The coil pack, plugs, and wires were replaced in Feb. On the freeway, it sometimes seems like power is lost and if a hill comes before me than I usually lose about 20mph. I replaced the K & N air filter with a paper one to rule that out. The fuel filter was replaced in Feb. as well. No funny smells, all fluids where they should be. Cat is good. Had a coolant leak with no evidence but found a hose at the back of the engine that may be the cause for that as the headers are right under it and may evap the coolant as it lands on the header. Not sure what could be issue. Ran seafoam through crank and fuel and the problem minimized and after a follow up tank of premium and back to the 85 the problem is still prevelant. Oh, and when idling I can rev smoothly all the way through my RPM range. Any help or advice would be great. Thank you!

RammerX

I recently had a problem with low idle and stalling very often. It threw the code P0505(Idle Air Control) and P0770(solenoid E malfunction). All I did was clean the throttle body and butterfly plate and it took care of both problems! Now it doesn't stall and my idle rpm went from 400 up to 650. And yes it accelerates faster now from a stopped position. Just sharing my experience with low idle in hopes maybe this can help you...?