Check Engine

[2.5driver]

Yesterday my check engine light came on in my Tacoma. With all the offroading I do in that truck, I figured my filter might need to be cleaned
(K&N), so I figured I would start there. I took it out of the airbox, and it was filthy. I cleaned it all up, let it dry, re-oiled it, and put it back in. Now, does that light have to be reset for it to go off, or does it do it automatically when the problem is fixed? My light is still on. I know that with some vehicles you can reset it by simply disconnecting the battery. Any help would be great.

I have other things I want to spend my money on than taking it in and having it fixed, but if thats what i comes down too, then I guess I don't have much a choice.

[cuda_tmaxx]

just run up to an Autozone or similar autoparts store and in most cases they will go out to your vehicle with a diagnostic device that can determine the cause of the CEL and can clear the code for free. It wouldn't be surpising to find a cylinder misfire code tripped due to the filter being dirty and fouling a plug

[TRX in Tampa]

Take it to AutoZone they put that cheap little code finder on it for free. Then if it is a code for like the air filter or the gas cap not being on tight enough, you can have them reset the check engine light.

[TRX in Tampa]

Nice Cuda exact same time, 10:00

[cuda_tmaxx]

or the gas cap not being on tight enough,

During my short 4 day employment at Autozone i probabaly saw that code over 100 times.

hmm...i didnt think it posted so i clicked again and a thing popped up saying it was a duplicate to a post in the last 5 minutes and will not be displayed, I have never seen that before

[arceeguy]

If you fixed the problem, the MIL will go out automatically after you use the truck about 5 times. (complete cycle, cold engine to fully warmed up) The trouble codes will still remain in the computer for a while.

I just ordered a PC based OBDII scan tool from auto enginuity to help me troubleshoot an intermittent stalling problem on arceegal's car. Hooks up to a laptop and has "flight recorder" capability. Dealer wanted $300 to hook up their black box, so I figured I would just buy the tool myself. If you wrench on cars a lot, it might be a good investment for you. It pays for itself the first time you use it.

[chickenhawk]

Definately a good investment now that you can't get inspected with the light on.

[1fast3.3]

Couple of things. Yes if you disconnct the battery it will erase the current freeze frame data and dtc off the buss line and in most cases the keep alive memory, just disconnect for about 20 secs. If there is still indeed a problem the CEL will be tripped after two failed trip cycles. Also if cleaning the air filter was to resolve the problem, which the only codes that would set would be a P0174 Bank at lean adapt limit, it would clear itself after 3 completed and passed drive cycles.

On another note: Your vehicle is equipt with a MAF-Mass Air Flow sensor. It uses a heated wire that senses flow of air accross it by how much it cools the wire. Often people use too much oil on a K&N filter which allows the oil to be plastered accross the hot wire in the MAF and causes it to read incorrectly and often sets a P0174 or it sets no code at all but you notice a fuel mileage decrease.

No matter what you decide to do as far as getting the light out, I would go to autozone and let them retrieve the current code. They use a very cheap and crude code checker, but they atleast do it for free. At my shop we charge about $68 to retrieve and diagnose the code, which is waived when a customer makes the repair or in cases where the gas cap may have been loose and set an P0440 Evap leak detected. I own 3 scanners and between the intial cost and yearly updates I have over $7000 invested. Of course they have the ability to do a lot more then run simple codes.

If you do decide to retrieve the code and post it back on here, I would be happy to give you a hand as much as I could. I work on any makes, but specialize in drivability and enhanced diagnostics for Honda/Acura, Toyota/Lexus, GM, Ford and Mopar.

Arceeguy: What year, make and model? may be a common problem or a TSB for the problem.

Have a Merry Christmas and Happy and Safe Holidays

Nick

[arceeguy]

Arceeguy: What year, make and model? may be a common problem or a TSB for the problem....

It's a 1997 Dodge Stratus 2.4L I4 - about 60,000 miles.
I checked the fuel pressure, and was lucky enough to have it quit in the driveway while the gauge was connected. No drop in pressure, so the fuel pump is probably okay. I took it to the dealer, who then replaced the coil module. It didn't fix the problem. Whatever is causing the stalling is not setting off any DTC's, so the dealer recommended hooking up his data logger and letting my wife drive for a few days. Since the diagnostic was so expensive, and not put towards the repair, I decided to purchase the Auto Enginuity PC diagnostic tool for 100 bucks less and do it myself. It seems like the dealer is content with replacing components one at a time until he finally gets it right, all on MY dime. This is why I do it myself whenever I can. Everytime I go to a dealer or local garage around here the job is never really done right. The one place I trusted for the last 18 years closed last year when the owner retired.

My initial though was that it was a bad crank sensor, but the dealer says that a bad crank sensor will definitely set off a DTC and light the MIL. Hopefully, the data logging feature of this scan tool will find the cause.

On a side note, if the car is on the highway, it will not stall - but it will hesitate for a fraction of a second. When sitting in traffic, the engine will stop, but will immediately restart with a twist of the key. If the cruise control is on, the cruise will drop out when it hiccups. Doesn't matter whether the engine is hot or cold, but the problem is getting worse. It will hiccup at least once in a 20 minute drive now. I guess if we keep driving it, it will just quit running altogether and the problem will be easier to find. Although, I'll probably be divorced before that happens.

Sorry for hijacking this thread, but if a professional mechanic is offering advice, I'm taking it!

[aussiek2000]

its always free for us a the dealership. my dad is a mechanic and owns two, $5000 GM scanners.

[2.5driver]

Sorry for hijacking this thread, but if a professional mechanic is offering advice, I'm taking it!

Haha, I don't care. Its all stuff that I'm learning from to.

Thanks for the help everyone. 1fast3.3, I'll take it to Autozone on Tuesday, and have them get the code for me, and then post it here. Thats if the check engine light is still on by then.

[ktiller]

i own a Code Scanner and Comp for automotive...Love it it has saved me alot of money in repair cost knowing what the problem is....i think i paid $300.00 for it a year ago....

[GlowThunder]

my chec kengine came on lastyear and my car ran really bad. i have OBD1 Autozone does not have the right scanner to read the codes. my friend at work has a 500$ snap on scanner with all the hook ups and programs for almost every car, it was the MAF that went bad. 150$ with tax to replace it and it was a reman one .

best to get a OBDII if your truck requires a OBDII scanner and get it checked out for sure.

[gatman90]

Take it to AutoZone they put that cheap little code finder on it for free.

those computers used to find codes on vehicles are certainly not cheap. my dad is a mechanic in business for himself and that "cheap little device" you speak of is 10,000$ (snap on brand, and it costs several hundred to several thousand dollars a year to update them). my dad charges people when he has to use that just because he has to have some way of making some of the money back that he spent on it.

[cuda_tmaxx]

those computers used to find codes on vehicles are certainly not cheap. my dad is a mechanic in business for himself and that "cheap little device" you speak of is 10,000 (from snap on). my dad charges people when he has to use that just because he has to have some way of making some of the money back that he spent on it.

Actually the ones at Autozone is cheap. It cost $100 and it will refrence the code number that has tripped. You then have to look in a little book or on the computer as to what the code is. This is what we used. It will only do OBD II, but that never seemed to be a problem

And yes the MODIS is expensive at $7700, but it is well more than most people will ever need.

[gatman90]

yea well my dads been a mechanic for over 37 years and with cars being as advanced as they are today you almost have to have a good computer to check for codes and stuff. then you have to get the update cards for different cars, especially the foreign ones. thankfully if it ever breaks, which it has before, snap on fixes it for free and send you another one to use while the original one is being fixed.

[1fast3.3]

Autozone does indeed use a rather "cheap" code checker. Usually in the range of $100 or so and it only reads the codes. I own a Snap-On Solus scanner $2600 new $3600 with european capabilites, aslo runs $1000 a year to keep it updated. Also own a GM Tech2 was $2800 new also cost about $1200 a year to keep updated and alow me to access the internet reflash GM ECM's. My 3rd Scanner is the new Mopar StarScan $5500 with 3 years of updates. Our shop also has a Modus $6700 with Snap On trade in, and the new Ford IDS with a PDA about $4800.These are all professional scanners and do a lot more then just retrieve codes. They all allow me to data log, graph and play back data, and offer numerous functional control over the onboard computers included reflash prgramming and updating.

In new cars even on the lower scale devices are control by modules. On a 2006 Corvette for an example, when you press the door handle their is no mechanical connection the the car. A micro switch relays a signal to a module that then tells the door actuator to open. That goes the same for window switchs, headlamps, wipers, ect,.

Arceeguy: The cam sensor and crank sensor are both common repairs. The crank usually does not set a code, but the cam often does (P0340). In fact in 12 years I have never seen a crank sensor code. It really stinks when you lose a trustworthy shop/mechanic, there is just too many snakes out there, especially in the dealerships. Worse time to go to a dealer....when they are slow (don't have and cars to work on) they will "find" things to replace and all to often when you really do have a problem they just hang parts. Not to say so much that they are bad auto techs, they just work in a corrupt organization.

[2.5driver]

In new cars even on the lower scale devices are control by modules. On a 2006 Corvette for an example, when you press the door handle their is no mechanical connection the the car. A micro switch relays a signal to a module that then tells the door actuator to open. That goes the same for window switchs, headlamps, wipers, ect,.

Wow. Thats interesting. I never knew that.

[2.5driver]

So today I took my truck to Autozone, and found out what was wrong. Heres a list:

EVAP emissions control leak
EVAP emissions control malfunction
EVAP purge flow fault
EVAP circuit malfunction

Guess it wasn't the air filter...

[1fast3.3]

I assume the codes were P0440 Evap System Leak and P0446 Evap Purge Flow Malfunction. This is actually a relatively common failure on these. Of course I am not there to test and confirm, but the Evap Vacuum Switching Valve is usually the culprit. Toyota recommends when replacinging the Evap VSV that you replace the charcoal canitser.

Again please take my " over the internet diagnosis " as set in stone. Usually a loose gas cap will only set a P0440 evap leak detected. If they cleared the code for you, then ride it out and see if it comes back. If it indeed does come back on, you then may want to seek a reputable shop to get it repaired. Evap codes are not the end of the world, the evaporative system is there to not allow Hydro-Carbons to evaporate from you gas tank into the atomsphere, further polluting and adding to greenhouse gases.......well, ok in the long run malfunctioning evap systems could very well be the end of the world

Nick

[arceeguy]

If you do a lot of offroading and the MIL came on after an offroad adventure, maybe a purge line or evap hose got damaged and needs to be repaired/replaced. I had the unfortunate experience of running over a scissor jack that was in the middle of the highway. It embedded itself in the charcoal canister, and a P0440 code was set within about 20 minutes of driving. I guess I was lucky that it didn't take out the gas tank, which is right next to the canister. I repaired the hole in the charcoal canister with some "Goop" shoe repair cement and cleared the code. I suppose the system is working and I am not going to be responsible for the destruction of the earth through global warming.

[2.5driver]

I assume the codes were P0440 Evap System Leak and P0446 Evap Purge Flow Malfunction. This is actually a relatively common failure on these. Of course I am not there to test and confirm, but the Evap Vacuum Switching Valve is usually the culprit. Toyota recommends when replacinging the Evap VSV that you replace the charcoal canitser.

Again please take my " over the internet diagnosis " as set in stone. Usually a loose gas cap will only set a P0440 evap leak detected. If they cleared the code for you, then ride it out and see if it comes back. If it indeed does come back on, you then may want to seek a reputable shop to get it repaired. Evap codes are not the end of the world, the evaporative system is there to not allow Hydro-Carbons to evaporate from you gas tank into the atomsphere, further polluting and adding to greenhouse gases.......well, ok in the long run malfunctioning evap systems could very well be the end of the world

Nick

I don't think it was my gas cap that would have set it off. Its one of those where once its tight enough it starts clicking. I always tighten it until it clicks, so, I don't see how it could have been loose. We're taking it in to Toyota hopefully sometime soon to get the problem straightened out.

I think Arceeguy is probably correct. After one of my adventures offroad, I'm sure something got messed up and set all those codes off.

[arceeguy]

Got my OBDII scan tool today. Hooked it up to my laptop and started logging all major engine parameters. Drove for an hour and the engine didn't hiccup once. Pretty cool tool overall, gonna drive the heap some more tomorrow to see if it'll stumble or stall. I'm still guessing it is the crank sensor, especially since 1fast3.3 has seen these fail without setting a code.

[GlowThunder]

Got my OBDII scan tool today. Hooked it up to my laptop and started logging all major engine parameters. Drove for an hour and the engine didn't hiccup once. Pretty cool tool overall, gonna drive the heap some more tomorrow to see if it'll stumble or stall. I'm still guessing it is the crank sensor, especially since 1fast3.3 has seen these fail without setting a code.

arceeguy where did you Buy your OBDII from? and the price? i need one for my 1995 ford probe.

[arceeguy]

Go to autoenginuity.com and look at their OBDII scanner. The basic model retails for $249.99 but you can buy them on eBay for $199.99. (direct from the manufacturer) You can upgrade the software to get enhanced coverage, and that adds manufacturer specific powertrain, ABS, air bag and chassis capability, but that bumps the cost to around $700. I bought the basic system, and may upgrade the software if I need to in the future. They also have versions that work with PalmPilots or Pocket PC based PDA's.

Here's a good one - I got pulled over when I was driving because the cop saw the glow from the laptop screen and thought I was watching a DVD. If he had pulled me over for speeding, I could have shown him that I wasn't because had vehicle speed monitored and logged.

[GlowThunder]

Go to autoenginuity.com and look at their OBDII scanner. The basic model retails for $249.99 but you can buy them on eBay for $199.99. (direct from the manufacturer) You can upgrade the software to get enhanced coverage, and that adds manufacturer specific powertrain, ABS, air bag and chassis capability, but that bumps the cost to around $700. I bought the basic system, and may upgrade the software if I need to in the future. They also have versions that work with PalmPilots or Pocket PC based PDA's.

Here's a good one - I got pulled over when I was driving because the cop saw the glow from the laptop screen and thought I was watching a DVD. If he had pulled me over for speeding, I could have shown him that I wasn't because had vehicle speed monitored and logged.

are you serious? Pulled over (WOW) Did he write you a ticket?

thanks for the info on the scanner.

[arceeguy]

Naaaa - no ticket. He had never seen a PC based scan tool before. I wasn't driving erratically, he said that he's seen a lot of folks watching movies on portable DVD players and that'll earn you a ticket for sure.

The passenger cabin must have looked pretty bright as I drove by. Along with the laptop, the Pioneer head unit I have (DEH-P6800MP) has very bright blue backlighting and I haven't figured out how to dim it yet. I think the display is supposed to dim when I turn on the headlights. Oh well.....

[cooleocool]

On the subject of those scan tools, my dad has been looking at getting one. Probably one like you have arcee... Sounds very similar. Same for the price. My over drive light on my Explorer flashes every so often. Still drive fine. I'd imagine that one of those tools could be pretty nifty! I'm hoping he gets one!

That's funny about getting pulled over for your laptop... .

[1fast3.3]

Tom if your overdrive light has flashed, a transmission code may be stored in the memory of the ECM/TCM. 1995 was a cross year you may have an EEC-IV system or OBDII if you get a code you will get an idea of what may be going on.

Often on Ford transmissions when the fluid gets dirty and burnt the TCC may intermitent slip on engagement, this may not be felt by you but the ECM/TCM sees the difference in RPM. Often a transmission flush is the cure.

Just my 2 cents.

Nick

[arceeguy]

Nick - My car stumbled and stalled today, and each time it did, the scan tool lost communications with the car. (Except twice, when I lost all monitored parameters except RPM and throttle position, but eveything else went dead. I needed to restart the software to connect again) What do you think, ECM or not? Is there anything else I can check before shelling out 200+ dollars for a rebuilt ECM? Also - how much should I expect to be charged for flashing the ECM?

Thanks!

[cuda_tmaxx]

arceeguy-if it is easily accessable, remove the ECM and open it up. My 4 cylinder Dodge dakota did the exact same thing. On a whim i pulled the ECM, after replacing the TPS, Hall Effect Pickup and coil, and there was a mouse nest inside. I replace the ECM and the problem solved

[arceeguy]

The ECM is right up front. It is probably a cold solder joint somewhere on the circuit board. I've repaired a few Ford CCRM modules because of bad internal solder joints, but since this is my wife's car, I figure a remanufactured ECM would be the best answer. If she gets stranded, she'll want a new car. It's my job to make sure that the car never leaves her stranded. I don't like buying new cars, and she wants a Toyota Prius - which currently go for thousands over list price because of demand. I'd go for a Jetta Turbo Diesel though - very good mileage. I had an old Rabbit Diesel that went over 250K miles and it was still running strong when I sold it!

[1fast3.3]

Sometimes you can confirm an ECM problem by taping on it or wiggle the mainconnector with it running, car may stumble. I can honestly say I have never replaced ecms in those particular mopars, but jeeps and some 94-98 dodge trucks had problems with dropping a buss line or losing reference voltage. Most common Mopar issues, crank sensor shorting out and pulling down the buss line, knocking out communication. Also a bad ASD relay (auto shut down) can malfunction and drop power to the injectors, ignition, ecm, ect.

[NJ racer1]

If I may make a suggestion.Remove the ECM,but keep the connectors attatched.Start the car and flex or twist the ECM,as 1fast3.3 touched upon.When the car shut off,you said you were still able to view RPM and TPS.What were they indicating?I will check ALLDATTA at work tomorrow for an service builetens on this problem and post my findings.Does your scantool have a Freeze Frame feature,so you can see what everything was indicating at the time of the problem?

[Nitronaught]

You all make it sound so complicated. It's really simple.

When the Check Engine light comes on, you are supposed to get a check from your check book and fill it out for your engine. At least that's what usually happens when I see that light on my truck or car.

[arceeguy]

Update:

It is the ECM for sure!
I borrowed an identical car from the motor pool at work, and I swapped ECM's. The stalling problem moved from one vehicle to the other.

Sure I have to write a fairly large check to buy another ECM, but overall, I spent a lot less than having some garage replace sensors one by one, only to determine that the ECM needed replacing. It was a pain to diagnose because it took 3 hours of driving for the symptoms to show up (the stuff that drives auto techs NUTS) and I wasn't really sure of my results. It could have been a flakey ground connection or bad wiring harness causing the ECM to glitch out too.