Check engine light

[expobronc]

Okay guys I know this is too impossible to answer directly, just looking for ideas.

I just bought a 98 AWD V8. on the way home the check engine light pops on, after I got on it a LITTLE, very little. I can't get it off. Cold, hot dont matter. The thing idles like a top, might have the SLIGHTEST bit of hessitation, plenty of power on the highway, etc. What does the CEL indicate? Does it check the oil? coolant?
My 92 had a seperate light for oil. All guages seem normal, except for maybe the volts seem low. Could it indicate I need new plugs? Exhaust smells just fine. all connections under the hood are good. Coolant was Black so I did a flush... I have the old eec scanner but not the obd.....

Like I said I know this is soooooo vauge, but and input is great

 

[jonny 5]

Have autozone run a free check up on your truck and tell us what codes they picked up

 

[Alec]

You need to get the codes. It's OBD II.

 

[expobronc]

oh and also it idles about 850-900

 

[jonny 5]

Good timing, 3 posts in a minute
Any other symtoms? weird noises, fumes, etc....

 

[expobronc]

nope, runs clean and all...

I cleaned up the IAC, looked SPOTLESS anyways, but cleared the comp and fired it up drove it for about 15 mins and the CEL is off, but I won't be surprised if it comes back on...

 

[Jake's Dad]

I own my second X, I had a 96 and now I have a 97. On both trucks the CEL light came on intermittent, and it was the 02 sensor both times. Not a huge deal - you can still drive it - but replace it as it will eventually take the catalitic converter out which is costly. Do a search on these threads and you'll get a bunch of info to help you diagnose it. But first - get to an autozone and have em give you the code!!

JD

 

[jasonb]

ok.. autozone did the freebee hookup for me and this is what i was told.. he said it was running lean and it didn't give a code for a sensor being bad. something about bank 1 and 2. basically that the mixture of oxygen and fuel was off. he said to check my air filter and the MAF, but the filter SHOULD be fine. forgive that lame description, it was just after i got off work today after learning that we got a huge project so my mind was on the possible bonus. anyway, i have noticed a slight sluggishness (is that a word?) when i hit the gas and it idles just a shy big choppy. not enough that many people would notice but i do.
anyway, could any of you give me advice on what to start with. i can usually fix stuff when i know what the problem is, i just can't diagnose for crap. thanks!

 

[Alec]

usually running lean is due to the MAS, O2 sensor, or FPR.

 

[Jason_25]

jason, with your 99 you can pretty much rule out the FPR for now. The first thing you should do is check for vacuum leaks as they can cause the truck to run lean. If you really wanna get serious with it, buy a vacuum gauge. If there are no apparent leaks, clean the MAF thoroughly. If that doesn't do it, check back with us. How many miles do you have?

 

[jasonb]

i have about 59k on now.
where do i need to check for leaks and is the gauge the only way to find vacuum leaks? i guess i can swing by this weekend and pick up a vacuum gauge. i can't find my darn chilton's or i'd look some of this up in there too. i had planned to clean the MAF this weekend also if my parents don't hang around too long! thanks for the replies.

 

[Jason_25]

Well sometimes you can hear the "hiss" from the vacuum leak if you have good hearing. Also, you can trace all the vacuum lines all the way to the device that they run to and check for leaks along the way(time consunming).

 

[jasonb]

thanks again.. my hearing is pretty darn good so i'll try that too.
well i know what i'm doing this weekend!

 

[expobronc]

isn't there something about spraying carb cleaner or something around the engine compartment and listening for the engine to speed up??

 

[Jason_25]

I beleive that's only if the intake manifold gaskets are leaking. Which brings up a good point. It could be possible that your intake manifold gaskets are leaking jason. I'm not certain but here's what Ford recommends to find out: spray propane around the intake manifold and listen for the engine to speedup. You may want to ask Robert, because he's the expert on all the SOHC recalls though.

 

[jasonb]

i didn't know they made spray propane. ya learn something every day!
jeez.. i was just hoping it was the fuel cap again.

thanks for the info guys. i'll track down Robert if the MAF cleaning doesn't work.

 

[Jason_25]

Originally posted by jasonb
i didn't know they made spray propane. ya learn something every day!
jeez.. i was just hoping it was the fuel cap again.

thanks for the info guys. i'll track down Robert if the MAF cleaning doesn't work.

Heh maybe they don't! I was just saying get a small bottle of propane and slowly release it around the intake manifold.

Sorry for the confusion.

 

[Robert]

Yes, Ford recommends "introducing propane around the upper and lower intake manifold while the engine is running". This was their recommended procedure to verfiy the leaking lower intake manifold o-rings long before it ever made it to ONP 00M12. They don't say to listen for the engine speeding up. What the procedure has you do is monitor the short term fuel trims and watch for sudden changes while introducing the propane. I used a small propane torch that I bough from Walmart for about $20. It had a torch attachment that screwed onto the top of the 1 lb bottle of included propane. It has a black knob to turn the propane on and off. It works excellent for doing this (much easier than my original idea of lifting my barbeque tank up onto my engine ). I couldn't hear any noticeable difference when I did it to mine but I did see a change of about 15%-20% whenever I moved the propane around my manifold. You will need an OBD-II scanner that is capable of reading Ford Enhanced OBD-II parameters to do it though.

Did Autozone give you the actual codes? If they were a P0171 or P0174 then I would look at the lower intake manifold o-rings before I did anything else. Better yet, you are still under the mileage and time limits for the extended warranty. Let Ford fix it on their dime. It wouldn't hurt to troubleshoot it first yourself though just to be sure Ford doesn't try feeding you a line.

 

[jasonb]

so there was a recall about the leaking manifold gaskets? i didn't know that..
how much does one of these scanners cost? and no he didn't give me the actual codes. should i go back and try to get them? i really appreciate all the replies guys.
unless something comes up, i'll probably try cleaning the MAF this weekend. if that doesn't do anything, i'll go back and get the codes then try the propane thing. thanks again. any further input is welcomed!

 

[Robert]

No there never was a recall on the lower intake manifold o-rings. However, there is an Owner Notification Program (ONP 00M12). It was released around November, 2000. What it does is extends the warranty on the o-rings to 6 years, 72K miles for the SOHC. The camshaft tensioner update is tied into the same ONP. If either of these items fail within the extended warranty period, Ford is instructed to replace both at no charge to the owner. You should have received a letter from Ford when the ONP was first announced unless you weren't the owner at the time. Do a search for 00M12 and you should find the letter that I scanned in and posted. Print it out and go to the dealer if you suspect the problem to be them. Mine went out at about 50K miles. After I confirmed the source, I took it to an independant shop to let them replace the o-rings under my aftermarket extended warranty. Eight months later, the ONP was announced.