Ok I know that OBD-II's are supposed to be for 96 and up. I have a 95 Explorer Eddie Bauer and I think it may be an OBD-II. I have a connector under the dash and it has 16 slots. There are metal pins in slot 4,5,7,and 16. Can anyone tell me if this is OBD-I or OBD-II? Maybe someone that has the same year and model as me. My second question is Can a scanner be used without the check engine light coming on? I went to AutoZone and asked this guy(I always get stuck with this jerk) if they could hook a scanner up to my explorer because it is idling funny. He said "is your check engine light on", I said "no", then he said "well the only way the scanners will work is if the check engine light is on". Personally I think this sounds like a bunch of bull. Ive changed the spark plugs, IdleAirController and the TPS Sensor. Besides idling funny, whenever I hit the gas pedal somewhat aggresively my RPM's go Down and then Up, sometimes when I do this (at a stop light) the explorer stalls out. It is an automatic by the way. Other times the RPM's just drop really low, like 400RPM and then they jump back up. Thanks in advance for any ideas

 

I have a mazda with both OBD-1 and 2 plugs and it a 93. The OBD-2 is most likely part of the wireing and may not be hooked up all the way that year. Look under the hood down around battery back up to the fire wall and see if you can find OBD-1 plug. (2) YES, you can but you wont get any thing. Need the light on. Have you checked for vacuum leaks around intake and so on??

 

No I havent checked for vacuum leaks yet....what is the best method?..I have heard of spraying WD-40 or Propane around suspect areas and if the RPMs jump up that is where the leak is.

 

95 was a transition year for computers in Fords. It essentially was and OBD-1 system, but the vehicle was also wired as if OBD-II was present. If you look under the hood near the fuse box, you will also find the old familiar OBD-I connector, and codes are pulled from the system using this one, using the OBD-I methods. Hooking and OBD-II scanner to the connector will most likely result in a failure to initialize or some such message from the scanner. By the way, on this year, the PCM is called a GEM and it incorporated several different functions into 1 package. It was only produced for this one model year and then was replaced by the fully OBD-II systems.

This link should answer your questions. It contains some of the most detailed info I have ever seen on Ford eec systems and component tests.

http://www.carsoft.ru/avtorepair/gtest.pdf

Dialtone

 

Dialtone is correct. My 95 has the OBDII under the dash, but it's inoperative. Use the EECIV connection under the hood. Also, OBDI scanners are cheaper than the OBDIIs, but are worthless after '95.

 

thanks you guys. That link you sent me is awesom dialtone. 183 pages. Can I pull the codes without the check engine light on?

 

Re-read the linked document. In it you will see there are several types of tests available, and they are not dependant on the check engine light being lit.

Test 1 is the Key On Engine OFF self test. In this test, basic sensor function is verified to be within acceptable parameters for a non-running engine. Run this test first, work ONLY on the first code given (if any) and re-run it till you get an all pass condition. Then move on to the next test.

Test 2 is the Key On Engine Running test. This test verifies the entire engine management system can function as a whole in a dynamic setting (engine running). There are several steps and some steps require your intervention to verify some of the sensors (throttle sensor comes to mind, brake on, if equipped and power steering pressure monitor to name a few). Again, work ONLY on the first code given, then re-run till all pass condition. If you think you may still have problems or intermittant faults are present after a drive cycle that may or may not produce stored codes, then move on to the wiggle test.

A third test is called continuous monitor mode (or Wiggle Test). This test is VERY usefull to find intermittant wiring problems. In this test, the PCM looks at all the sensors for intermittant operation signals. If one is detected, the PCM immediately kills the engine. The tester moves around the various sensors and wiggles or otherwise flexes the wiring harnesses and connectors in an attempt to induce the intermittant fault. When the engine dies, you know you have a problem and a good idea of the general location to look at in detail.

Other subtests are for verifing the base engine timing and the cylinder balance tests, but I am not too familiar with their operations in detail.

It has been my experience that if you get thru tests 1 and 2 above with no faults detected, the vehicle should run fairly well. If driveability issues are still present, or codes are stored after a period of time driving, then you will need to investigate the possibility of intermittant faults.

Hope this helps.
Dialtone

 

The 1995 and even 1994 transition years i have read about say that some models, T-brid maybe, came with OBD-II. I wasn't aware Ford actually wired other models like this but ran the EEC-IV OBD-I. Interesting.

Direct answer - Yes you can always check for stored codes. The CEL may never come on for a code to be stored. Typically, the CEL will not stay lite very long anyway. So 99/100 time when the Autozone ask someone if the light is on, the answer is, well no not now. So why do you think these guys are working at Autozone for $8/hr anyway - I don't think they are brain surgens.

Now another thing, unless I missed it, I didn't see where you disconnected the battery or anyone else say to do so. You need to do this with any one of the components you changed. Reason is to not just clear the codes to see if they come back but mainly to clear KAM of all stored learned correction factors. They PCM had tried to adjust A/F mixture and spark curve tables when it notices components where going bad. This is a really cool feature to keep your car running OK while you get to defer maintenance - though it was actually incorporated to keep emmisions low because the car wasn't being maintained. Whatever, half full / half empty. So I think if you haven't disconnected the battery for 10 min's, do this now and you'll probable see a noticable affect on performance.

Also check this link - it's really good at describing the Ford EFI system and EEC-IV/V's in general.

http://www.fordfuelinjection.com/

 

I have seen a lot of discussion of the usage of the scanner, does anyone have a particular one they would suggest? Any that I should stay away from would be good to know. Danny

 

For my OBD-I system, I just use a voltmeter and paperclip. Read the codes by counting the meter sweeps. Has served me well for years and you can always use a good analog voltmeter around the house / car for testing other things.
For my ODB-II system, I decided to go with a device that runs off a serial laptop computer port. It is just a simple protocol converter the speaks ascii (computer side) and converts it to the OBD-II portocols. It works on Ford, GM, and ISO (foreign) and is able to produce a virtual dashboard display as well as allow you to see the O2 sensors plotted in real time.
The device is called BR-3 OBD-II interface, is available from http://obddiagnostics.com , and the cost is around $95 including shipping. Software is free and available on the site for download. You can even download it and take a test run before you buy to get a feel for how it works and its features.
Dialtone

 

I use an Autoxray www.autoxray.com

I just had it upgraded so it reads OBD-I and OBD-II. They have various models from ~$139 - $600

 

Carb. cleaner, WD-40,blaster something in that area will work. Check the intake good, have seen some post on the same problem and the fix was snugging the bolt down on the intake. But check with the spray first. Also check the vac. lines too.