Hesitation just off idle (and only in gear)

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Re: Hesitation just off idle (and only in gear)

Gary Lewis
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That's not much wobble on the vacuum, but I can hear the bobble in the RPM and see it on the vacuum.  I think you have an EGR problem.  Tomorrow may tell.
Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: Hesitation just off idle (and only in gear)

ckuske
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Well, jury is out for me to do another round of testing.

First, I capped vacuum line that attaches to the EGR itself.  The stumble at fast idle is still there, no question.  

After I tried each configuration a couple times, either I stopped noticing the difference, or the truck had gotten its way into a better state.  I was never able to make it stall, so I suppose that is good.

Also tried capping off the vacuum that goes into the solenoid to remove the EGR and solenoid both - again is seemed better but it is hard to say for sure.  

(Vacuum Source -> Solenoid -> EGR Vacuum Line -> EGR Vacuum Connector)

I tried capping some other paths off, no improvement.  I also hooked the vacuum gauge up to the EGR vacuum line, and verified there is only vacuum applied through the solenoid after the truck is warm, and you advance the throttle.

I guess I should remove the EGR and check it on the bench etc, and make sure everything is clean, seats well (EGR fully closed?) etc.
Chris

'84 F-150 XL 2WD Flareside, 302 w/ AOD transmission, Motorcraft 2150 feedback carb w/ CA Emissions, EEC-IV w/TFI, factory A/C, speed control - Info about me and my truck - My project thread
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Re: Hesitation just off idle (and only in gear)

Gary Lewis
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Yes, I think that would be my next step.  Perhaps the valve is, as they frequently are, carboned up and won't fully close.
Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: Hesitation just off idle (and only in gear)

ckuske
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Ok, I pulled it.  It basically looks brand new still.  I pulled vacuum on it and the valve seems to move freely as well.





I did notice that the EGR cooler should have a gasket on both sides.  I didn't remove it off the manifold yet, but if there is a gasket there, I sure didn't see it.  Either it's fallen apart or isn't there.  That would be a red flag (I think).  If you slide the cooler on the bolts and try to mate it against the manifold, there's a small "clank".  You would think if a gasket was there, it wouldn't do that...

It looks like the same gasket should be on both sides of the cooler in the drawing below.  I felt inside the cooler with my finger and got some carbon out.  I guess I'll pull that next (how deep is this onion?).  Before I go down that rabbit hole I suppose I should measure the EVP voltage to make sure that isn't throwing the ECU off...




Chris

'84 F-150 XL 2WD Flareside, 302 w/ AOD transmission, Motorcraft 2150 feedback carb w/ CA Emissions, EEC-IV w/TFI, factory A/C, speed control - Info about me and my truck - My project thread
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Re: Hesitation just off idle (and only in gear)

Gary Lewis
Administrator
I think the lack of a gasket is the issue. You’ve had a leak there.
Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: Hesitation just off idle (and only in gear)

ckuske
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Agreed!  Fingers crossed.

To be clear, there was a gasket mating the EGR to the cooler. From cooler to the manifold is TBD ( an hour or two hopefully), it doesn’t  appear so.
Chris

'84 F-150 XL 2WD Flareside, 302 w/ AOD transmission, Motorcraft 2150 feedback carb w/ CA Emissions, EEC-IV w/TFI, factory A/C, speed control - Info about me and my truck - My project thread
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Re: Hesitation just off idle (and only in gear)

ckuske
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This post was updated on .
No such luck.  There was a gasket there, not in great condition, but it was there.

I've ordered two fresh ones from Amazon, they'll be here Tuesday.

I took the cooler off and gave it a bath with hot water and Dawn dish soap.  It looks much better.  There was a fair amount of carbon, but not enough that I thought it would have caused an issue.  But it just got Roto-Rootered, so it should be good for years to come.

On Tuesday I'll put everything back together, check out the EVP sensor, and unless a miracle happens by then, go down the smoke test route.  It still feels like a vacuum issue, so that's the track I'll stay down.

Coincidentally with all of this, my original power steering pump gave up the ghost finally.  So, putting a replacement on with the rest of my day today...
Chris

'84 F-150 XL 2WD Flareside, 302 w/ AOD transmission, Motorcraft 2150 feedback carb w/ CA Emissions, EEC-IV w/TFI, factory A/C, speed control - Info about me and my truck - My project thread
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Re: Hesitation just off idle (and only in gear)

Gary Lewis
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Well, like Edison you know one more thing it isn't.  

Bummer on the power steering pump.  That's a messy job.  
Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: Hesitation just off idle (and only in gear)

ckuske
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Yep, I know eventually the problem will make itself known.

On the power steering thread, I just got the old one off, and got the pulley off too.  First time I've ever done that.

I used my brake bleeder vacuum pump, that made it much less messy!
Chris

'84 F-150 XL 2WD Flareside, 302 w/ AOD transmission, Motorcraft 2150 feedback carb w/ CA Emissions, EEC-IV w/TFI, factory A/C, speed control - Info about me and my truck - My project thread
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Re: Hesitation just off idle (and only in gear)

ckuske
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This post was updated on .
Ok, I need to put my EGR/vacuum stuff back on so I can start bleeding the power steering and test it.

So, I checked the EVP.  My Haynes manual says resistance between VREF and EVP signal pin is supposed to be "slightly less than but no greater than 5000 Ohms".  Mine is around 4550. So fail, I think.

Next, EVP signal pin and SIG RTN should be "slightly greater than, but no lower than 100 ohms" but it is 1200 Ohms!

I think I found the problem?  I will take the EVP off the EGR and make sure the pintle isn't stuck somewhere...

I imagine a reading this far off could really cause the ECU to do stuff that shouldn't be happening...

Chris

'84 F-150 XL 2WD Flareside, 302 w/ AOD transmission, Motorcraft 2150 feedback carb w/ CA Emissions, EEC-IV w/TFI, factory A/C, speed control - Info about me and my truck - My project thread
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Re: Hesitation just off idle (and only in gear)

Gary Lewis
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I think you are onto something.  Good luck!
Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: Hesitation just off idle (and only in gear)

ckuske
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It may not be *the* thing, but it’s definitely *a* thing.

I just removed the EVP from the EGR and measured again. (I noticed that when removing it, it felt “spring loaded”, meaning the pintle was depressed just be being installed.)

Anyway, with it removed the measurements are now 4880 Ohms and 683 Ohms. Still out of spec, but closer.

Looks like I need to hunt for a new EVP…
Chris

'84 F-150 XL 2WD Flareside, 302 w/ AOD transmission, Motorcraft 2150 feedback carb w/ CA Emissions, EEC-IV w/TFI, factory A/C, speed control - Info about me and my truck - My project thread
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Re: Hesitation just off idle (and only in gear)

ckuske
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This post was updated on .
Got the new EVP in.  The new NOS Motorcraft one registers less resistance between pins than the one that was on the truck.  It still doesn't match the Haynes guidance though...

Old One:

692 Ohms between SIG RTN and EVP SIG, and 4940 Ohms between VREF and SIG RTN on the old one. (the RTN/SIG was reading 1200 ohms the other day, so not sure why it is reading 692 now.  I did however push the sensor rod in a few times, maybe it has a problem not returning fully out?)

New One:

520 Ohms between SIG RTN and EVP SIG, and 4440 Ohms between VREF and SIG RTN on the new one.

Now to try it and see if anything is different after starting...

Also, the new one came with two different gaskets... I am unsure if both are needed?  It seems the wider one would work.  Maybe due to different vehicles?  I would put both on, the smaller one sites on top of a flat region of the wider o-ring, but I since this sensor is based on depth into the EGR, I am worried it might throw it off.





Chris

'84 F-150 XL 2WD Flareside, 302 w/ AOD transmission, Motorcraft 2150 feedback carb w/ CA Emissions, EEC-IV w/TFI, factory A/C, speed control - Info about me and my truck - My project thread
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Re: Hesitation just off idle (and only in gear)

Gary Lewis
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I'm guessing that the different gaskets are for different vehicles.  So if the wider one fits yours I'd go with it.

Good luck!  
Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: Hesitation just off idle (and only in gear)

ckuske
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Thanks, will try it out shortly!

I realize I ask questions that are fairly obvious, but I try to not assume too much.  There is a lot of tribal knowledge that you only acquire through the School of Hard Knocks, and I rely on you guys to hopefully steer me in the right direction.
Chris

'84 F-150 XL 2WD Flareside, 302 w/ AOD transmission, Motorcraft 2150 feedback carb w/ CA Emissions, EEC-IV w/TFI, factory A/C, speed control - Info about me and my truck - My project thread
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Re: Hesitation just off idle (and only in gear)

Gary Lewis
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You are right to ask questions.  The only dumb question is one you didn't ask.

Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: Hesitation just off idle (and only in gear)

ckuske
Administrator
This post was updated on .
Well, not fixed.  I ran the KOEO test first, it came back clean (phew).  

I ran the KOER test next, and got all sorts of goofy codes, some of which weren't even in the reader manual.  I convinced myself last time when this happened that I didn't set the reader up correctly. (I use https://a.co/d/aW87eVS)

I thought the procedure was:

1.  Warm truck up, then turn ignition off
2.  Connect test connector and single (ground?) wire to terminals on code reader
3.  Turn code reader on
4.  Turn ignition on, start engine
5.  Press Test button on reader
6.  See Cylinder ID code
7.  Wait for 10 code
8.  Press accelerator

In reality, I ran the test several times - most of the time the Cylinder ID code didn't come out, the 10 code came out sometimes, and got odd codes such as 3, 4, etc.

I had this happen before, but altered my steps and it was much more coherent (got Cylinder ID test, 10, and then only one code, 35).  Most of the steps I find online relate to a test light, maybe I'm getting something wrong in the translation.

Apart from my KOER problems here (likely my fault), the stumble is still there at fast idle.  I didn't back probe the EVP connector to check the voltage differential between pins.  Maybe that is next.  One other note, the first time I ran KOER, the engine died during a part of the test where I assume the EGR is opened.  After the engine died, there was a repetitive sound of a "click" (but deeper than that), about 8 times a second.  Constant, no variability in timing etc.  It sounded to be coming from the EGR, but that doens't make much sense.  It was definitely from that area, I tried to stick my head close but couldn't isolate it exactly.  I kind of thought maybe it would have been the thermactor solenoids, but they were silent....

I still have the truck on jack stands from bleeding the power steering, I'll lower it and take it for a quick drive in a day or so to see if the main problem is addressed.
Chris

'84 F-150 XL 2WD Flareside, 302 w/ AOD transmission, Motorcraft 2150 feedback carb w/ CA Emissions, EEC-IV w/TFI, factory A/C, speed control - Info about me and my truck - My project thread
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Re: Hesitation just off idle (and only in gear)

ckuske
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Just ran it again - maybe it's not warmed up enough?  I waited until the thermostat opened etc.... about 4 to 5 minutes of running time, about 90 seconds at 2000 rpm.  Choke was fully open.

Anyway, the code this time (with no Cylinder ID again...):

20
47
2
5
47
3
85

2, 5, and 3 are out of bounds.  85 doesn't seem to apply to trucks at all.  I am out of time today, I will drive the truck before posting again.  Thanks for hanging in there.
Chris

'84 F-150 XL 2WD Flareside, 302 w/ AOD transmission, Motorcraft 2150 feedback carb w/ CA Emissions, EEC-IV w/TFI, factory A/C, speed control - Info about me and my truck - My project thread
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Re: Hesitation just off idle (and only in gear)

ckuske
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I got a smoke machine and ran a smoke test.  I taped the carb up, and ran the smoke through the brake booster line.  I found one 'T' vacuum fitting that had a leak.  Fixed that leak.

OK, I took the truck out to warm it up for a KOER test, and drove it around tried to see if the hesitation was better.  At first it wasn't... same as usual.  After about a minute of driving, it was essentially gone.  The stumble at fast idle is still there when in park (even after pulling back in, putting it in park, then revving to 2000 rpm).  It's not there when driving...

Moving on to try to KOER test again:

I got the cylinder code (8) just fine this time.  Ok, great... maybe I didn't warm it up enough last time.  A little bit went by, then got the goose code (10).  Hit the gas, codes started coming out.  Some puzzlers still:

31,35,82,4,41,47,92,94

I turned everything off, ran the test again.  Same results up to the codes coming out.  I got code 32, then 35.  Another code was being read, and my scanner display went completely blank.  Like dead.  Batteries are fine.  Disconnected it and turned it back on... lit right up.

So now, I am not sure what to trust.  Is my reader bad (maybe)... is my ECU bad?  Maybe.  KOEO still works fine every time, no issues there.

So, I've fixed one vacuum leak and the hesitation in drive is better, but my KOER tests are goofy and the stumble in park is still there.  I am getting a little frustrated - I feel like I am reaching my diagnosis limits.  But, the one guy I've taken the truck to before hasn't been able to address the hesistation issue in drive after he's seen it three times (it was lower on the list compared to other problems).  He's kind of the "go to" guy around here for this vintage of car, and I don't want to start shot gunning and trying random people.  

I'm not sure where to go from here to be honest.  I suppose buying a new reader or just getting a test light is the next step...
Chris

'84 F-150 XL 2WD Flareside, 302 w/ AOD transmission, Motorcraft 2150 feedback carb w/ CA Emissions, EEC-IV w/TFI, factory A/C, speed control - Info about me and my truck - My project thread
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Re: Hesitation just off idle (and only in gear)

grumpin
Which reader do you have?
Dane
1986 F250HD SC XLT Lariat 4x4 460 C6-Sold
1992 Bronco XLT 4x4 351W E4OD
1998 GMC Sierra SLE K1500 350 4L60E
Arizona
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