I have been trying to track down a miss on my '98 E350 Van with V-10. It is my understanding that this is OBDI. I have the Harbor Freight code reader and am trying to understand what it is telling me.

I am using the section "On-Board Mon. Test"
I have 6 option to chose
$45
$4A
$4B
$50
$51
$52

I have been looking at the $51 data as it has 5 ID's and I am hoping that this is somehow telling me about the coils maybe.

This is what is displayed under $51
ID: 01 (goes from 01-05)
MOD: $10
MEAS: 3
MAX: A3D
MIN: ------
STS: OK

So with everything cleared I get no measured counts and status OK. I can drive around lightly for a time and all OK. Then I go up a hill and apply the breaks slightly to load up the engine. Here is what I get:
ID: 05
MOD: $10
MEAS: FFFF
MAX: A3D
STS: Fail

I also get a few MEAS on an ID on occasion.

I can't see the fault in real time but I drove a little and then checked and nothing. Then did the loading of the engine up the hill and checked after and got the Fail. It will reset after turning off and restarting van.

So basically can anyone help me understand what this is telling me and what the different modes are and what is ID 01-05. Any input would be appreciated.

Michael

 

Well, I went to Advance Auto and used their code reader a Actron 9580 and it had the same mode but instead of just 5 ID's they had all 10. It shows cyl 5,6,7,8 all failing. Now the van does not run that bad and yesterday I replaced boots on 5,6,7,8 as they looked looked the worse and a few of these coils were the Accer Coils. Maybe I need to replace the Accer's with some of the older coils I have laying around with new boot and see if that helps.

Ideas?

Michael

 

Since you replaced the boots, have you checked with the code reader again?

 

Yes. I have also now replaced the coils with different one's. Still misfire on 5-8. Frustrating. Getting ready to check plugs and maybe compression and leak down.

Michael

 

Sounds like you're a candidate for plugs, boots, checking the COP connections from the chassis wiring and of course those COP's as well.

Over and over here we've read of issues with the aftermarket COP's dying prematurely, Accel's being one of the most reported for failing early. I myself am running a mix of OEM (264K miles) COP's and Granatelli's which have been somewhat problematic since they were first DIY installed.

Just an opinion but when the engine is loaded and those faults occur it tells me the COP's are weak but don't show a fault enough for the PCM to discover it during idling or normal driving. (I'm just guessing and highly subject to being wrong on this!)

BTW that Actron CP9580 is a great scanner tool for the money!

Hope its nothing more severe or costly!

 

I installed all new plugs yesterday and changed coils around again. All the Accel's are off the engine and I still get the same misfires in 5-8. So with new plugs, coils moved and replaced the same cylinders are misfiring. Or at least having misfire events. There is no check engine light as you stated. I have checked all the connections to the coils and injectors. These misfires don't occur right away. Maybe after a few miles of driving.

Michael

 

Check for vacuum leaks, and one other thing although it should generate a lean code, clean the MAF - you could be running on the hairy edge of stoich and those cylinders are just unlucky enough to be lean enough to misfire.

 

Here's a helpful link to this process: https://www.ford-trucks.com/forums/1...eanup-day.html

HTH

 

The MAF was replaced about 15K miles ago. I looked at it yesterday and both wires were clean as a whistle.

Thanks for the ideas. Keep them coming.

Michael