When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I am trying to troubleshoot a misfire on my truck and I am using a laptop based scanner for the first time. While I have figured a lot of it out I am not sure about some of the data I am seeing and would like a confirmation.
I am running ScanMaster-Elm 2.1 on my windows 7 laptop using an ELM 327 scanner. No CEL or codes come up on the scanner.
Initially when connecting with mode 06 (Monitored Test Results) I am only seeing misfire data at a very low rate on cylinder one. If I let it run then I am seeing $56 counts rise up and left long enough will trip a fail. I think $56 has something to do with total misfires but not really sure how to read that data or what to make of it. I have downloaded Ford's OBD2 manual for this year and it doesnt help much in this area.
I swapped COP from cylinder 1 to cylinder 5. Still got the exact same data as before so I cleared all codes using the scanner. Cylinder 1 went to zero but $56 still counts up like before. I am going to reset the computer by unplugging the battery and then taking it for another drive. Then rescan and see what I have.
Does this sound right? Am I missing something or am I misinterpreting the data? Oh and yes I do see that I have a potential issue with the EGR downstream pressure reading. Hoses and tubes look good, I will go further with it after I get this misfire fixed or misfire troubleshooting leads me to the EGR.
EGR downstream reading is too low actually. That is if I am reading it correctly? Using fords data to convert it means I am reading something like 2.5 inH2O instead of I think 12 ish but my memory could be off. I looked at both hoses and bottom side of sensor and they look fine. I plan on putting a gauge on that hose and then pressurizing that hose to the value it is expecting to see if it is the sensor or a clogged tube.
Yeah I was reading same thing. But that is all they say about it and frankly it is unclear to me. Total misfires or is it just a counter for how many events it has tested? If a counter why would it have a fail condition?
Not running okay this morning, misfire still there. I will scan again tonight.
How many miles do u have to log before it will generate mode06 data after a hard reset like this?
There was some good info in that Taurus thread I posted above.
Seems it's one of those counters that needs to get to a certain point before the PCM starts to really take a good look at misfires.
"Look at the picture again and notice the value for TID $56 and the maximum threshold. I have obviously failed this test! These are potential misfire events. An event is any disruption in crankshaft acceleration, which can be caused by going over bumps in the road, the A/C compressor clutch engaging, or even just because of noise in the crankshaft signal. In order to count as a misfire, an event has to occur during a misfire check and have a certain acceleration profile, so the vast majority of events are not considered misfires (even if they are being caused by one). If more than a certain number of events (3000 in my case) are logged in a certain period of time (every key cycle) the PCM will do a 1000 rev misfire test to find out if the car is truly misfiring, and what cylinder/how often it is misfiring. This can only happen after the crankshaft profile correction portion of the misfire monitor has completed. Profile correction monitors crankshaft acceleration during a fuel-cutoff deceleration to "learn" the exact tooth profile on the crank position wheel. After a KAM reset or code clearing it requires you to coast (no brake) from 60-40mph 3 times to complete the monitor.
"
Now, is your '99 REALLY OBD-I? Does it actually say that on the underhood sticker?
You have an EGR, do you have an O2 sensor after the catalytic converter? (Just to make absolutely sure what's going on here).
Unless the vehicle was manufactured to California/"Green state" requirements (OBDII), it's OBDI. Many, many 99-07(?) Super Duty trucks are OBD1, not, OBDII, which really complicates some of the troubleshooting since the OBDI calibrations are sparsely documented by Ford. The label on the underside of the hood gives the "as-manufactured" configuration.
TID$56 is supposed to increment, it's normal as noted in the OBDII manual. It's just a counter of "Cylinder events tested and number of events required for a 1000 rev test". I suspect your software's tagging of that entry as a "fail" is erroneous as is the TCCA poster's interpretation.
The "limit" of TID$56 will be 3000 if a V6, 4000 if a V8, and 5000 if a V10 as those are the number of "ignition events" required to represent 1000 revolutions of the engine. This is not a PASS/FAIL test although the software writer assumed it was.
it means I am reading something like 2.5 inH2O instead of I think 12 ish but my memory could be off.
See page 25 of OBD manual:
"Typical EGR hose check malfunction thresholds:"
"DPFE sensor voltage: < 7 in H2O, > 7 in H2O"
You do not have a test results that indicates an EGR problem, you have a "false" red flag.
Well I should make a correction, I swapped 1 with 6.
After clearing scans and computer and a day of driving I scanned again. Results showed 6 now had the misfire. Swapped in a good coil I had laying around. Rinsed and repeated and now 6 is clean. 10 now has a really low count like 65 so this could be a fluke or maybe just a really low level misfire. Either way it should be good for this trip this weekend.
I will scan again when I get back and go from there. On to the EGR next, I will likely go into a dealer first and pick their brain. Thanks for the help!
I did thanks for the info, that is why I am going into the dealer....
To ask their opinion. I have had people tell me both sides so I will see what they say and make a descision from there.
Like I said at the beginning I am trying to learn how to use this software. Sure I want to fix the truck but in the long run it will payoff if I learn how to use this new tool properly.
Good luck finding a person at the dealership who 1) will talk to you and 2) knows what you're talking about.... Usually, you'll never get past the service writer. One of his/her jobs is to keep you away from the technicians who are doing the actual work on the vehicles.
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level
Slideshow: The VelociRaptor Expedition gains a lift, upgraded suspension, Brembo brakes, and trail-ready equipment while retaining the stock 440-horsepower EcoBoost V6.
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.
