I have a 99 Ranger. My "check engine" light came on today. I have 71,967 miles on my truck right now. My friend told me that most Ford vehicals "check engine" light comes on near 72k miles for a tune up. Is this true? I doubt it is, sounded like crap to me, i was just being nice and humored him just so I could change the subject haha. My truck is running like normal, I can't tell anything wrong, so I don't even know what to look for? Any suggestions, I'm all ears guys. I don't have an Auto Zone within two hours of me, so getting it scanned there for free isn't an option. I might just go ahead and get new plugs, wires, coil packs, thermostat and coolant tomorrow and work on it all day. Anyway- anything else I could check out? Thanks for the help...later

-kirk

 

That is total BS. The light is on because a trouble code is stored in the PCM and there are several hundred of them. You won't have a clue what's wrong until you get the code pulled by a dealer, parts store or whatever.

You can order an inexpensive OBDII code reader from Harbor Freight for $39.99 (sale price).

 

or it could be like our 1985 camaro where the engine light comes on and stays on yet there is absolutely nothing wrong with the car - we even had the dealer of all rip off places to go to run it, and no codes..... for like $300 they said theyd rip the dash apart and redo the wiring to the light..... 1 cent worth of electrical tape fixed that problem....

 

^1985 didnt have OBDII though, so there would be no codes lol.. Back on topic, i'd suggest like bob said, order a cheap OBDII Code Reader, even walmart sells them, if you go to the dealer, they are gonna charge you an arm and a leg to diagnose it.. i think its like $80-90. So why not just buy one, then you can charge your friends to check out their vehicles :)

 

for the last year or so my light has been on i want it to burn out...lol stupid egr insufficient flow...lol

 

There's one off Wesley drive Rt.15, about 45 minute drive. Especially if you're gonna buy a bunch of tune-up parts, it's worth the drive.

My 84 F 150 had ODBII, I used one of those walmart testers often on it. I found it one day in the clearance rack for like $5. I was like "Score!!".

 

According to obdII.com "All cars and light trucks built and sold in the United States after January 1, 1996 were required to be OBD II equipped. In general, this means all 1996 model year cars and light trucks are compliant, even if built in late 1995." and it lists pre-OBDII as 94-95.. I've never seen an older car below 96 with an OBDII port, Wierd because '84 didnt even have EFI.. it was optional on the 302 in 85 though. Here is a link on what wikipedia says on OBD.. pretty interesting stuff..

 

Yup, there was a plug right under the engine. It had a lil cap on it that even said OBD. It was a 300 I6 carb'd. Granted it pulled a limited amount of codes but it was there nonetheless.

 

Its most likely an egr code.

 

I bit the bullet, i went to Wal Mart and bought my own OBD2 scanner. This thing is pretty cool! It couldn't be easier to use. I threw two codes


PO133 - O2 Sensor Circuit Slow Responce
P1131 - Lack Of HO2S11 Switches - Sensor Indicates Lean

So all I need to do is get a new O2 sensor? About how much is one and is it hard to put in? I'm new to Rangers, I'm a long time GM guy, don't know a whole lot about Fords just yet. Thanks!


*edit* posted the 2nd code

 

It could be a mixture problem but, given the miles on your truck, it could also be the O2 sensor. The "11" in the HO2S11 says that this is the front passenger side sensor near or in the exhaust manifold. If it is dead, chances are that the driver side won't be far behind it.

These can often be tough to remove since the sensors live in a 1500F environment and the threads tend to seize. My only advice is to use a good wrench and be careful not to round off the flats.

 

what do you do if you round off the flats?

 

You can strip it and you'll have a hell of a time getting it off then!

 

my old 98 had the exact same at the exact same mileage (no joke). the truck was running perfect but the engine light.. i took it to my mechanic and he ran the same codes you did (except O2) but he debated with himself for a while and decided to try to clean the MAF. about 2 weeks later the light came back on, and we replaced it. worked for a while and about a month and a half later the light was on again. well i was gonna ignore it but i knew that i needed to change spark plugs, so i changed and the light never came on again.

 

mx98ranger- that's what i'm gonna do, i'm gonna do a complete tune up while i have the time right now, i have off tomorrow, so hopefully i can get it all done!

 

my 99 did the same thing at that mileage, it was the 02 sensors and i changed them both. than at around 90k the light came back on and it said "egr flow infuffient" and "egr flow excessive". talked to a ford mechanic and he had the same problem with his ranger. he said it was the DPFE sensor, a 50$ fix. but now the truck has 106k and the lights on again and throwing the same code. you guys think its the EGR sensor?