idling funny

idling funny

well my car has been idling wierdly as of late, either too high (round 1300) or too low (500) and when it goes to low it feels like my car is going to stall out, what does that sound like? could it be the sparkplugs? im going on a road trip this weekend and kinda wanna figure out whats been causing it so i dont break down in the mountains somewhere.

would the book i have show how to clean the map sensor?(as far as i know i havent cleaned it) and the ecu was reset when i got my new transmission.

What did you do or touch last?

I don't think you can clean a MAP sensor - MAF I can see. A weird idle could be caused by a dirty throttle body, clogged PCV valve, and/or worn plugs, plug wires, or bad coil. Can also be as simple as a bad tank of gas - sometimes you can get a couple of bad tanks, might try a different gas station. Could also be clogged fuel injectors - a decent fuel injector cleaner like Redline, Chevron or Valvoline Synpower can sometimes help.

Any CEL that falshed recently? How's the overall fuel economy - has it dropped significantly from before? Other than weird idle - does it seem to be down on power, missing (misfiring) at speed? What is the car's mileage - when was the last time you got a decent tune up on the car?

I had a strange problem like that. My car also shook a LOT at low speeds..... turned out is was a broken motor mount. I had that same strange idle problem, but once I got the mount fixed, it worked just fine.

But I"d go with what fishexpo posted.

There's no such thing as a bad tank of gas. Gas is all the same. It just depends on the additive they add to it. It does sound like clogged injectors or maybe a bad fuel pump. Check all your maintenance factors like mentioned above.

rollatuner110 added 0 Minutes and 50 Seconds later...

But his car isn't shaking. It's got intermittent idling speeds.

i thought he meant maf. well my 98 doesnt have a maf i think? last thing i did was clean the air filter the other week.

ill check the throttle body tonight, and the pcv valve, plugs are a little white and by a little i mean barely noticable, but my step dad says they are fine. ill try that fuel injector cleaner next time i get gas.

ok so to dig this thread up from the dead.

idling funny again this time upwards of 1500 and as high as 3000 i had an issue witht he check engine light last night one of my spark plug wires was disconnected?? wtf i dunno i plugged that bitch back in and added a half quart of oil till i can change it next weekend. i couldnt seem to get the pcv valve out this time i dunno my fingers were pretty chilly as it is snowing outside. was going to pick up a scan gauge 2 to see if any codes pop up at me. oh and another thing is when i have my foot on the clutch it will idle higher then if i dont....

so far im thinking
-dirty pcv
-plugs misfiring
-something with the clutch
-something with the fuel pump?
-engine is dieing =\
-user error to the maximum

bump again. high idling today.

Yeah, 3000 RPM idle - that is a bit fast. Did you pull the code for the CEL - was it indeed a misfire code, ie. P0300 - P0304 code?

Did you remove the plugs to "read" them? If yes, how did they look? Might also be a good idea to check the plug gap as well - even off a 10s to 100s thousandths of an inch can cause a misfire.

How many miles are on this engine? Usually a good idea to just replace the PCV valve every 30K miles to avoid problems, at the very least - need to clean it with a solvent to make sure it "rattles" fine. Same with the hose connecting the PCV to the intake manifold - should be in good shape and make a good seal (no vacuum leaks).

You can do a quick test with the PCV - disconnect the hose and try running the car. Shouldn't be able to hold an idle at all - should run like $hit. If there is no change, then the PCV is clogged.

Also, when is this problem most noticeable - from a cold start, after the engine warms up a bit, warm engine restart, coming to a stop from high speed, etc.? I'd double check the throttlebody to make sure it is clean.

If all checks out OK - could be the AIC valve on the throttle body (Air Idle Control valve) - if that is clogged or stuck, the car will not idle evenly. Can get really nasty with carbon and varnish buildup. Just be careful of the electronics on the side - you don't want to screw with that = expensive paperweight.

Good Luck.

ok well, i figured out what was casusing it, i took out the cruise control when i bought the car and disconnected the cable that is on the trottle body, unfortunatley i cant take it completely off without replacing the trottle cord and body and blah blah, it was stuck somewhere causing the high idles

as far as pcv valve, i couldnt get it unplugged same with the hose. i didnt want to pull on it too hard i dont know whats wrong with it normally it comes out pretty easily.

hehe, well cruise control sucks on an stick =P and it was an aftermarket unit so it was acting all funky with my ECU and caused it to short out like 5 days after i got the car

Yeah, that PCV hose can be tough to get off - especially if it is still running the original PCV. The hose gets dryed out and gets stuck on there pretty good. Not sure on the earlier 1ZZ-FE Corollas - but my PCV was screwed into the valvecover - not a press in fit. I know they have two part numbers for the 1ZZ-FE PCV - not sure if they are interchangeable.

The hose, just loosen the spring clamp, give it a couple of turn to see if it will break free from the end of the PCV. Especially if you notice the engine starting to slowly increase engine oil consumption or the throttle body getting gummed up very quickly - check the PCV out first.

i will try it when it gets a bit warmer out. i think mine screws in at least it looks lke it does so i will also try that. its not the orginal i have changed it before but the hose is still original. might be looking at getting an oil catch can.

oh and i was reading in the repair manual and it said using 5w30 in the higher mileage engines can lead to more oil burning can anyone confirm this? if so i will switch to 10w30.

what do you mean by the throttle body dumping?

Motor oil weight of 5W-30 is a little thinner, then the 10W-30 - easier to get pulled past worn or stuck rings, can get past worn or dried valve seals. Also, some 5W-30 oils have larger amounts of viscosity modifiers present compared to 10W-30 oil - this may make the 5W-30 more susceptible to thermal breakdown. But with newer oils, conventional and synthetic - not much of a problem like before - in fact some conventional oils have better specs than some full synthetics.

Couldn't hurt to try some 10W-30 - should still be safe to run, unless you consistently see sub-zero temperatures for extended periods of time. Also those high-mileage oils tend to have more additives to help swell up valve seals and trap/neutralize more contaminants - many are also synthetic blends to boot - may try a crankcase of the stuff and see if it does anything to the oil consumption. But don't read too much of the "high-mileage" oils marketing hype - my 2002 has almost 140K miles, doesn't burn a drop of oil, I generally run Mobil 1 5W-30 + OEM "tall" filters. Lately, it has been any synthetic oil that is on sale - car is still fine.

As for the throttle body gumming up - the excess crankcase vapors gets pulled into the throttle body to be burned off during normal operation - in some cases, the amount of excess vapor can be extreme. A truck load of hot, oily crankcase vapor introduced to a cooler area like the throttle body - is a surefire recipe for deposits forming. Example of what I mean is here: http://www.trustmymechanic.com/parts_gallery/TBI_inlet.jpg

Also, doesn't have to be time consuming - they make all kinds of stuff to help do a good job. One is something called an "Intake Snake" http://www.run-rite.com/industry/9710.html A got a pair from a buddy of mine - they work pretty darn well. I'm trying to find the solvent they used, because it seems to be a lot stronger than what you can buy off the shelf.

hmm my throttle body does look a bit like that. i will look at some of that stuff to clean it out. thanks for the help man.

Could your IAC valve be sticking due to the cold climate...

iac?

your idle air control valve is on your throttle body. on your model its on the bottom.

Edit: Sorry, here are some instructions I saw over at Toyota Nation. Maybe it's something you can check. Click Here.

cleaned out my TB with a rag today, and cleaned my airfilter (which needs replacing) seems to be running a little better, will try to take a look at that IAC tomorrow after my brake job