Actron OBDII Scanners

Donnyj · Mar 9, 2007

Jarrett said:
It's a 2001 with the 3.0 OHV engine, about 80k miles. It shudders pretty hard when you put it in gear and start taking off. It runs a little rough at idle, but it mainly does it when taking off, either reverse or forward. As it's idling, you can kind of smell gas or like it's running rich, but not all the time. While on the throttle it runs smooth. Some of the research I've found on the internet says that the DPFE sensors are known to go bad, and could cause this problem. My wife bought the car from her Dad, and he kept all the records on it. It had the DPFE sensor changed at 36k miles.

I had a '97 F-150 4.6L V8 that did the same thing, except it would actually die out and it threw a code. I don't remember the code off hand, but it was something like "Insufficient EGR Flow". Changed the EGR valve, nothing. It turned out to be carbon buildup in the tube going to the EGR valve. Once I got that cleaned out, cleared the code and it never came back on and the engine ran great.

I know that's 2 completely different engines and different things can give the same symptoms, but I just have a feeling it could be the same thing.

The DPFE sensors are a very common problem, but they almost always set a code. Usually P0401. With the smell of gas I would check your fuel pressure just to see if the fuel pressure regulator is stuck. At idle the EGR system should not even be working, unless the EGR valve is stuck. The shuddering when putting in gear sounds like maybe a engine miss. Hard to tell without being there. The miss should get worse with increased engine load. I believe that engine uses a Mass Air Flow sensor mounted in the air intake. Another common problem. You would have to monitor the PID data from that sensor. The sensor has a Barometric pid data that is very important. Changes in altititude affect this sensor dramatically. Coming from extreme altitude sometimes this sensor sticks and the PCM still thinks you are at a certain altitude and fuel delivery and engine timing are affected. Reading the codes is only one piece of the puzzle, actually the easiest piece. If you can get somoene to pull the codes for you, maybe I can help you.

Jarrett · Mar 9, 2007

Donnyj said:
The DPFE sensors are a very common problem, but they almost always set a code. Usually P0401. With the smell of gas I would check your fuel pressure just to see if the fuel pressure regulator is stuck. At idle the EGR system should not even be working, unless the EGR valve is stuck. The shuddering when putting in gear sounds like maybe a engine miss. Hard to tell without being there. The miss should get worse with increased engine load. I believe that engine uses a Mass Air Flow sensor mounted in the air intake. Another common problem. You would have to monitor the PID data from that sensor. The sensor has a Barometric pid data that is very important. Changes in altititude affect this sensor dramatically. Coming from extreme altitude sometimes this sensor sticks and the PCM still thinks you are at a certain altitude and fuel delivery and engine timing are affected. Reading the codes is only one piece of the puzzle, actually the easiest piece. If you can get somoene to pull the codes for you, maybe I can help you.

This may be a dumb question, but will it give codes without the check engine light coming on? I'm under the impression that if the PCM gives you any code, the check engine light comes on.

hazmat · Mar 9, 2007

Jarrett said:
This may be a dumb question, but will it give codes without the check engine light coming on? I'm under the impression that if the PCM gives you any code, the check engine light comes on.

Short answer - Maybe

Very possible to have codes, but to not throw the check engine light. Depends on the how ford set it up.

You definitely want a unit that will provide real time parameter data - much easier to diagnose a problem.

Also - the "real" shop repair book is a big help. you can find ford's on DVD ROMs on ebay for a few bucks.

Donnyj · Mar 9, 2007

Jarrett said:
This may be a dumb question, but will it give codes without the check engine light coming on? I'm under the impression that if the PCM gives you any code, the check engine light comes on.

Not all the time. Sometimes you have what is called a pending code. It will show up on the scanner, but it has not turned on the light yet. Another valuable piece of info is called Mode 6 data. A good scan tool will let you see that info. Basically a snap shot of the PCM. A high end scan tool will let you graph the data, which to me, is alot better than just numbers. You could miss a glitch when just looking at numbers, but a graphing scan tool will let you see what is happening as well as history. I will look up any info I can find here at work on your symptom and see what results I get. Hopefully I can get you some info.

If you post the vin # or send it to me, I can run it on the factory systom for know problems and fixes.

I did run across a problem with the camshaft synchro assembly. This is the sensor that took the place of the distributor. I have seen where other shops have replaced this sensor and did not have the proper tool to line up the sensor when installing it. Vehicle still runs, but does suffer from hesitation and other concerns. Sometimes the sensor will not act up until it gets over 3,ooo rpm's.
The pcm only monitors that sensor up to 2,500 rpm's, so it would not turn on a light in that case. I have also seen where the air filter box was not sealed correctly after a air filter service. The top half of the box is not seated correctly in the lower half. This allows water ingestion into the MAF sensor causing problems or when the cooling fan kicks on it also sends hot air into the MAF sensor also causing some weird problems.

Tig · Mar 9, 2007

I have an ELMSCAN5. Connects to a PC and works great. It gives real time sensor data and I have used it to isolate a slow O2 sensor on my fathers motor home. As well as diagnosing EGR problems etc....
ScanTool.net - Home - Welcome to ScanTool.net
I see it now has a wireless adapter so you no longer need a laptop.

George2615 · Mar 9, 2007

I have the less expensive Actron CP9135. Its just a basic read and erase codes unit. I did however get an Email form Actron today on the new CP9180 and CP9190 units that read live data and many other uses. The 9180 price I was qouted is just under $200, the 9190 is just under $350 (200 off retail) and it does OBD I & II. Check their site for all the features of these models.

cp1969 · Mar 9, 2007

The DPFE throws a code. However, I didn't notice the engine running particularly bad, but was just thinking, "is this thing running right?" when the CEL came on. One thing about it, they are easy to get to on the 3.0---right on top of the engine. Looks like a 5 minute job (max) to replace one.

This very repair was what caused me to buy an Actron reader. I don't know which model, but they are regularly $149 and AutoZone sells them for $99 from time to time. If I'd had that reader, when the DPFE went out, it would have almost paid for itself from this one repair.

DieselPower · Mar 10, 2007

So true. Diagnostic time ain't cheap at a repair shop these day's. Then again neither is the equipment. For the shade tree wrench the handy little scanners can easily pay for themselves in 1 or 2 repairs.

Jarrett · Mar 10, 2007

cp1969 said:
....One thing about it, they are easy to get to on the 3.0---right on top of the engine. Looks like a 5 minute job (max) to replace one.

I wish! This one's on the top of the engine, but it's behing the intake manifold and un der the cowl. It looks like just to be able to get to it easily the manifold has to come off.