I know its a shot in the dark but my engine light came on the other night. Its a 07 v8 with 25k mileage. i started it up idled fine for 30 secs, then the idle started to get erratic up and own for 15 secs leveled off and the car ran fine. I drove for 10 minutes turned the car off for a couple of hours came ack started her up and engine light came on no rough idle or anything.
View 8 RepliesMy wife was complaining of the ESC light came on and off. Rough idle. Also has a check engine lite.
View 23 RepliesIt came on 2 months ago, took it to dealer, code said "erratic idle", it idled fine, smooth as it always has been, dealer turned of lite, said let him know if it comes on again.
View 2 RepliesI just purchased a 2005 elantra with 133k on it and she runs fine other than a slight erratic idle. And by slight I mean it will jump about 50-100 rpm idling and every blue moon it will jump up to 250 rpm sitting there. After idling for a while my CEL came on with the following codes.
P0507 idle air control rpm high
P0506 idle air control rpm low
P0170 fuel trim malfunction bank 1
P0121 throttle position sensor
What could be causing this? I took the iac off and cleaned it with maf cleaner but it didn't work.
My trucks symptoms include a illuminated service engine soon light, sometimes a high rpm idle, and sometimes a rough erratic idle. When a scan was done it indicated the oxygen sensor was defective. The issue is: which specific one (there are multiple oxygen sensors) or how could I check or determine the faulty one for sure. I am trying to economize and replace only the bad one myself if possible. I own a good multimeter, can it determine the bad one? 1999 F-150 4.2 Litre V6 oxygen sensor dillemna....
View 7 RepliesTwo days ago my 2005 T went in to have a heated driver seat switch replaced. Since getting it back we now have an annoying red light flashing from just to the top right of the Nav screen. Light flashes until either the radio is switched on or engine is started. I've checked the owners manual and forum but can't find any info on it.
View 6 Replies98 Honda Accord with 2.3L has 354,000 miles on it and up until recently ran like it was still new. Have developed erratic idle speeds. When it is cold it idles around 1100-1200 rpm. When the radiator fans are on or the A/C compressor is on it runs around 800-900 rpm. These are normal speeds and great. However, when the engine is warm/hot, in PARK, radiator fans are off, and A/C compressor kicks off, the idle speed drops to what appears to be about a rough idling 500 rpm's and the engine can barely stay running. I've attempted to look for the obvious. I own the Honda Shop Service manual if there is a particular component or most likely suspect area I should start at.
View 6 RepliesI have 120K on my 2004 V6 and have been driving with the Exhaust light on steady for about 1000 miles. Tonight after filling up at my usual Chevron with Techron Premium gas station, my engine started stalling and I lurched the 2 miles home. I took off the gas cap to see if reclosing it changed things and it did not. I had the coil pack recall work done 30K miles ago. I'm thinking fuel pump, having it towed to the shop?
View 2 RepliesI purchased a 2001 Jetta and it ran alright for a few days then all these problems started arising. The engine would not idle correctly and then a week later my EPC light started coming on. After all of that I have replaced the Throttle body ( Bosch) the MAF ( after market) and gas pedal ( after market). It ran fine for a day and then same issues. I had a mechanic relearn the throttle which had the Engine light go away for about a day. Now all the issues have came back. Here are the main problems.
1. Randomly lose throttle ( up hill, down hill, highway does not matter)
2. I randomly get stuck in park and cannot shift at all.
This is extremely troublesome since every time I lose throttle i have to put the car in park, shut her off and turn her back on to be able to drive. I keep getting the Throttle and MAF codes. I also checked on the recalled parts and they have already been replaced. I have read many reasons as to what would cause this but even the mechanic doesn't even know and I cant pay for him to check the electric. Also when driving if it is raining my car will not start or when it does it chugs. I was running through a puddle and after the water splashed the car basically would no longer run.
Filled tank with 8 gallons of 91 octane to top off. One hour later noticed car running rough at idle then check engine light comes on. Could it be the coil pack? Car has been running very well until now, and this Gremlin appears. I don't think it's the gas.
2004 -V8 Treg
52,000 on the odometer
At my wits end with a Tiguan problem that my dealership seems to be clueless ....
View 3 RepliesMy dads 05 f250 6.0 PSD. He says he'll take off in the morning and the fuel gauge will randomly drop to empty and trigger the low fuel light, but then also the Check Engine Light will come on. My brother did a code scan and no codes come up. Where we should be looking to remedy this one?
View 14 RepliesOn my '91 last week I was driving on the highway about 60-65 when all of a sudden the speedo dial started climbing to 70-75-80-85 and past. The odometer seems to be working ok? Still when I drive it still operates in the same manner. It never bounces around or falls back. The needle is sort of stable such if I maintain a speed the speedo will maintain even though it's incorrect. There is a slight wavering of the needle meaning it's not as stable as it use to be. With the odometer working I was wondering and don't know. Does the cable drive the needle or is it electrically controlled? I'm thinking of grabbing another instrument cluster it that is the problem, I'd like to know more about it and understand how it works so I don't just throw parts at it until it's fixed.
View 1 RepliesStarts rough but clears up after about a minute, I'm assuming the IAC is sticking. Whats the proper procedure for disconnecting and removing the cleaning and re-installing?
View 4 RepliesThe other day when it was raining out my car started idling below 1,000RPM/running rough. I was thinking it might be the coils, so I changed those, cleaned out my TB (Throttle Body), did a TB alignment (with VAG-COM) and now my car is idling at 1,200RPM and jumping up to about 1,600-1,800RPM, like I'm constantly revving it. I even swapped out my whole TB from my A4 and it still does it! If I disconnect the throttle position sensor it seems to idle normal.
View 2 RepliesI have a 94 Cobra Mustang with a 5.0. For the past few months it has had an erratic Idle and stalls when trying to idle. I've had a number of suggestions on how to fix it and nothings seems to work. I checked for vacuum leaks, changed PCV, new plugs, new IAC valve, tested ICM and throttle TPS and even adjusted idle. Still no luck.
View 3 RepliesHere is a YouTube video showing my erratic RPMs while idling in park, then pressing and releasing the brakes and gas to show what happens each time: [URL] ....
I just bought a 99 Explorer Sport. The history I know is that the truck has 200k+ miles on it, with the engine replaced. Replacement engine has 90k on it.
Was told the fuel pump, and serpentine belt (I think, he said "main belt") were replaced in the last few months.
The car was driving fine on the test drive and for the first few days of owning it. Then a clicking sound started form under the hood while driving.
I first noted the clicking while at a red light, and when I accelerated it stopped. Over the last week it has increased in frequency every day and now is almost constant.
This evening I was coming to a stop with my foot off the gas and when I hit the brakes the RPM went up, and car lurched forward before stopping gently. This kept happening so I drove home and took the above video. Video taken shows the RPMs jumping up when in park and going form idle to idle with brake depressed. when I rev the gas and let go, the RPMs fall, hang for a couple seconds, and then fall back to ~1000. The captions are very accurate, they show exactly when the brake or gas was pressed and when they were let go.
My obvious question would be WHAT IS CAUSING THIS? Also, ARE THE CLICKING AND THE RPMs RELATED? Finally, SHOULD I AVOID DRIVING IT? I need to drive it a few times through the next few days and I can't really avoid it unless it will mean serious damage.
Daughter's 2001 Santa Fe Delta V-6 2.5 engine, needed lower ball joints. Replaced the entire lower arms as more cost effective & actually a bit less work, for me anyway.
So While under it, see oil dripping down back of engine. Decided to replace valve cover gaskets. So I start to disconnect all the involved connectors, brackets etc to pull the Upper air intake to get to the rear cover.
While moving around, find most of the hoses & vac lines baked brittle and dried out and loose even tho clamped, so I replace all of those, plus the PCV valve., & the upper & lower radiator hoses as well. I only removed the upper 1/2 of the intake. I change out the cover gaskets, reassemble every thing, reconnect all the connectors. I noticed that some of the connectors could apparently be switched to other sensors, but since all the lines seemed so backed solid, they actually retained their positions to go back onto the proper sensors.(at least I hoped so & it seemed that way).
Anyway, every thing back together & tightened up, so I start it up & the idle is at about 3000 to 3400 RPMs. WTF? So I pop the throttle a couple of times by hand and finally it drops down to normal, then just as suddenly, it begins SEARCHING for lack of a better word, and starts racing upto 2600 rpm then drops to 1200 then up again then down again.
No check engine light or other idiot lights on. So I shut it down & check all the connections and hoses, nothing disconnected or left off or loose. I start it again, and it immediately begins running high & low searching for the idle again.
I shut it down again, and put the MacPro scanner on it and NO codes either set or pending. I next check the Haynes Manual I have for it, & the closest thing I can find to my problem says: Engine Lopes while idling or idles erratically 1) Vac leak 2) Leaking EGR 3)Air filt clogged 4) Fuel pump not delivering enough fuel 5) Leaking head gasket 6) Timing belt/sprockets worn 7) Camshaft lobes worn
By process of elimination, not #'s 2) According to service manual, there is no EGR valve on the 2.7, and I couldn't find one either, #3) Air Filter is new & clean, #4) ran fine before I worked on it & with the engine revving up to 34 or 3600 rpms, getting plenty of fuel, #5) Have had many head gasket problems over the years on many vehicles, never anything like this, and again, it ran fine until I worked on it #6 & 7) Doesn't seem to me to be a belt sprocket or cam shaft problem, as none of that was touched & again, it ran fine until I worked on it. This kind of narrows it down to #1, for me, but this is not like any vacuum leak I have ever come across in 45 years of auto repair. I have found & fixed many stumbling idles due to minor leaks but never had anything like this.
I next called a friend who owned an automotive machine shop & who I used to do work for, and now runs a highway dept garage for a municipality who has been a certified mechanic for many years, told him all the above & the only thing he could come up with was a MAJOR vacuum leak, like possibly the upper plenum gasket rolled up or got torn some how when I replaced the plenum and he suggested that I try a smoke test.
Scratching my head, I go back to the car, & break out my home made smoke machine that I use to successfully pinpoint leaks in emissions systems. I ran it for quite awhile, and found some light smoke leaking from somewhere down around the head, but due to the construction of the engine & no way to get the light to shine under the plenum, could only guess that he may have been right & that there may be a large leak down at the lower intake manifold to head gasket. Needless to say, I removed the upper plenum again, & this time also the manifold to heads, and the gaskets looked like they may possibly have leaked slightly between the ports, & quite possibly somewhere around the number 6 cylinder. So I cleaned the surfaces & am putting on the new gaskets that came in the set with the upper plenum to manifold gasket set.
My questions after relating all of this:
1) The 2 gaskets between the manifold & the cylinder heads have a blue stripe around all 3 cylinder port holes (appears to be some kind of sealant or factory applied silicone bead) & there are no markings of any kind anywhere on the gaskets, so do the blue stripes face DOWN to the heads or UP to the bottom of the intake manifold ?
2) Regardless of which way these stripes face, should I use any kind of high temp sealant around the port holes in addition to the gaskets, or just install them dry ?
3) Can the Idle Air Control on the Throttle Body Fail & affect the idle like the problem I am having, but NOT set a computer code ?
4) Can the Throttle Position Sensor affect the idle like this and NOT set a computer code?
5) I also found an electronic valve between the Air Intake & firewall, it is labeled PCV and has an OEM part number after that, I believe this to be the Purge Control Valve, which connects the TB to a plastic line which I believe runs down to the emissions canister under the vehicles front seats. Am I correct in thinking that even if this part had failed, it would have NOTHING to do with my erratic Idle problem, but would throw an emissions computer code?
I just picked up an 02 Hyundai elantra manual trans that needed a transmission. ran fine before I replaced transmission but after putting it all back together the car now how has an erratic idle. it will rev from 2-4000 rpms. I tried spraying for vacuum leaks idle didn't pick up any higher. replaced tps and iac and didn't make a difference. the only thing that did make any difference is unplugging map sensor. dropped idle to about 1200 rpm but ran rough. could this affect the idle.
View 1 RepliesI have an 01 f150 4.6 4x4 automatic with 90,000 miles. I have an erratic idle but it only happens when I am on the freeway well actually when I get off the freeway and stop. the idle will fluctuate between 750and then drop to 400 then back and forth til I get moving again. I replaced the IACV because it was doing the weird humming and vibrating the intake tube. The humming is gone but still idles funny as stated above.
View 4 RepliesThis weekend my CEL went on and stayed there. Everything seemed otherwise fine until yesterday, when the engine started running rough (like it is missing) and the CEL will flash on and off periodically. When I got home, the exhaust smelled like gas. I have an appointment with the dealer one week from today, and am driving my "spare" car in the interim.
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