Ford V10 slight miss

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1999 Ford V10 in a F53/F550. About a month ago I traveled some miles in a real downpour and all was well until the last few miles. I've read about the air filter becoming swamped and was parked for 5 days so figured it had dried out and all would be good. Trip home engine had a slight miss but no codes on the scangage and fuel MPG stayed normal. Fast forward to yesterday, started and run around the driveway and the miss is still there-no codes. Looked top of engine over, no vermin sign, no wires loose, plugs changed 12k ago and engine has 89k always run strong. I haven't noticed any loss of power either but can hear/feel this slight miss. Any ideas?
 
I had a filter get wet in a hard rain storm. Did you actually inspect the air filter? Did you check for trouble codes with a code reader?
 
I would replace the air filter if it got wet.
They take forever to pop a code. You could probably drive it another 20k and it would never pop.

Does it get worse under a load?

Not long after I bought my car it started missing going up a hill in OD.
I literally got another coil and moved it from cylinder to cylinder driving up and down the same hill 8 times until I found the right hole and it finally stopped misfiring.
Now a days I have a bluetooth adapter and Forscan on my laptop to look at Mode 6 data.
In Mode 6 you can see the actual misfire 'counts' from each cylinder. Its pretty obvious then to find the one that is missing.
 
Originally Posted By: tig1
I had a filter get wet in a hard rain storm. Did you actually inspect the air filter? Did you check for trouble codes with a code reader?

I did look at the filter-still looks new. My scangage is reporting nothing, well occasionallly I get a code for a bad O2 sensor but it's just a loose connection that corrects when I jiggle the wire.
 
Originally Posted By: Colt45ws
I would replace the air filter if it got wet.
I'll try a new filter
They take forever to pop a code. You could probably drive it another 20k and it would never pop.

Does it get worse under a load?
It's always under a load

Not long after I bought my car it started missing going up a hill in OD.
I literally got another coil and moved it from cylinder to cylinder driving up and down the same hill 8 times until I found the right hole and it finally stopped misfiring.
Now a days I have a bluetooth adapter and Forscan on my laptop to look at Mode 6 data.
In Mode 6 you can see the actual misfire 'counts' from each cylinder. Its pretty obvious then to find the one that is missing.

What does that cost?
 
Do you know what the O2 code is for? If its for the heater circuit its...meh. Not good but not a deal killer.
But if its the actual O2 sensor feedback then your fueling might be off on that bank.
It might be worth it to buy another O2 sensor and replace it rather than futz around with parts you know are bad.

If you have a laptop with bluetooth, you can get a bluetooth OBD2 adapter for like $20 from Amazon and the Forscan software is free.
 
Originally Posted By: Colt45ws
Do you know what the O2 code is for? If its for the heater circuit its...meh. Not good but not a deal killer.
But if its the actual O2 sensor feedback then your fueling might be off on that bank.
It might be worth it to buy another O2 sensor and replace it rather than futz around with parts you know are bad.

If you have a laptop with bluetooth, you can get a bluetooth OBD2 adapter for like $20 from Amazon and the Forscan software is free.

I don't remember what the O2 sensor codes were-have them written down somewhere. Do you have a link for the OBD2 adapter-there are alot of them?
 
Is the air filter exposed to the elements or something? I don't understand how an air filter can get wet short of driving through very deep water and literally submerging it.
 
Originally Posted By: dparm
Is the air filter exposed to the elements or something? I don't understand how an air filter can get wet short of driving through very deep water and literally submerging it.

It might be something with how the intake going into the air box is placed. I don't know.
It might be a good idea to reroute it.
 
Originally Posted By: Colt45ws

Now-a-days I have a bluetooth adapter and Forscan on my laptop to look at Mode 6 data.
In Mode 6 you can see the actual misfire 'counts' from each cylinder. Its pretty obvious then to find the one that is missing.


Man, that's the bee's knees.....
 
Originally Posted By: Linctex
Originally Posted By: Colt45ws

Now-a-days I have a bluetooth adapter and Forscan on my laptop to look at Mode 6 data.
In Mode 6 you can see the actual misfire 'counts' from each cylinder. Its pretty obvious then to find the one that is missing.


Man, that's the bee's knees.....

Yup. On my car it has to be misfiring like 24% of the time to set a light. But, if its only doing it going up a hill in OD, it will have to get much worse before it will set a code. In the mean time every time you go up a hill you reach for the 'OD Off' button to keep the load down. Very annoying.
Go into mode 6 and see 14k misfires on one cylinder vs under a few k for the others? Well, theres your culprit.
 
Your V10 will not set a check engine light for a misfire. It is basically an OBD1 system. I went through the same thing with mine - it ended up being a bad coil.
 
No, Rob is right, check it out.

So it sounds like the PCM is the same OBDII PCM but it doesnt monitor a lot of things.
It does sound like it is monitoring misfires, and COULD set a code but will never turn on the check engine light.
I still think accessing Mode 6 is gonna be your best chance of finding out which cylinder it is.
 
I ordered the Forscan app and the matching Forescan bluetooth ELM327 OBDII devise. I believe my '99 F53 has OBDII as it works perfectly with my scangage.
 
Originally Posted By: pkunk
I ordered the Forscan app and the matching Forescan bluetooth ELM327 OBDII devise. I believe my '99 F53 has OBDII as it works perfectly with my scangage.

Yeah it will because its using the same PCM and software as a OBDII PCM but they have some things turned off like cat monitoring which is required for OBDII so its "OBDI"
 
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