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Lugging at speed/No power at WOT

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ratdude747

Re: Lugging at speed/No power at WOT

Noted.

I will note that my idle got a lot worse when timing was adjusted (SPOUT disconnected). Maybe it was actually correct to begin with?

1984 F150: 300 L6, AOD, RWD. EEC IV / TFI, Feedback Carter YFA Carb. Stock everything but radio (for now).

85lebaront2

Re: Lugging at speed/No power at WOT

Administrator

Disconnecting the SPOUT simply locks the timing at the static setting, if you look at it once you plug the SPOUT back in, you will see the timing jumps sharply to the advance side (mine at 10° BTDC SPOUT unplugged, will go to 20 - 25° BTDC when reconnected. As a result, the engine slows down and in your case since it is carbureted the mixture gets a little off.

One important item to look at on the carburetor, with the air cleaner off, grab the top of the carburetor and try to move it, it should be solid, if it moves, look a the throttle body the float bowl area, if the bowl is moving on the throttle body, it will (a) destroy the gasket (b) cause mixture issues and (c) give accelerator pump problems.

Bill AKA "LOBO" Profile

"Getting old is inevitable, growing up is optional" Darth Vader 1986 F350 460 converted to MAF/SEFI, E4OD 12X3 1/2 rear brakes, traction loc 3:55 gear, 160 amp 3G alternator Wife's 2011 Flex Limited Daily Driver 2009 Flex Limited with factory tow package Project car 1986 Chrysler LeBaron convertible 2.2L Turbo II, modified A413

Gary Lewis

Re: Lugging at speed/No power at WOT

Administrator

In reply to this post by ratdude747

It is possible that the damper has slipped, making the timing mark off. I’ve seen that happen many times. In fact, my “new” damper on Big Blue is off by about 4 degrees.

Stick a piston stop in the #1 spark plug hole to find out.

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

ratdude747

Re: Lugging at speed/No power at WOT

Just for the heck of it, I "by ear" advanced my ignition timing back to approximately where it was when I bought it (have a timing light in the truck, but I didn't record where it was shown as). From the limited testing I could do over lunch break, it seems to run a bit better (no time to hit the highway, but far less lugging at 25mph). The idle is rough... but that could be a idle mix issue relating to the timing change (too rich?).

I'll determine #1 TDC and verify after work.

-------

The carb is solid. Already checked. No loose screws or leaks that I can find. I do know that when spout is connected, the timing should shift to around 20 degrees (which is what I observed). My assumption was that without the extra advance it was supposed to "not" idle well, hence why I didn't doubt my timing adjustment initially.

1984 F150: 300 L6, AOD, RWD. EEC IV / TFI, Feedback Carter YFA Carb. Stock everything but radio (for now).

reamer

Re: Lugging at speed/No power at WOT

Just found my loss of power at highway speeds as a plugged cat converter...

1986 F-150 Flareside 4x4, 351, 4-v, ZF5 speed. AC, Cruise, Tilt, Slider, Digital clock, Radio, Lariat seat, Pwr doors/locks

ratdude747

Re: Lugging at speed/No power at WOT

Already did a backpressure test, less than 1PSI.

1984 F150: 300 L6, AOD, RWD. EEC IV / TFI, Feedback Carter YFA Carb. Stock everything but radio (for now).

ratdude747

Re: Lugging at speed/No power at WOT

Yesterday I tried playing with the timing to get the intermittent rough idle (pinging?) out... which brought me to 10 degrees advanced from the 10 degree mark I originally timed to. No change to the idle fuel screw helped. At idle (A/C) off I'm get right at 20 in of vacuum.

Still lugs at 25mph... maybe this is a condition the AOD doesn't handle well and in such case, I just need to push until it downshifts? At 35mph or so it downshifts almost instantly when I give it a bit of gas. Or do I possibly have a valve body issue?

Haven't had time to test it on a long enough stretch of highway to test speeds over 55.

I might poke around on ebay and see if I can find a deal on a TPS... Edit- found a BWD one for $13 shipped... you gotta love liquidation sellers

1984 F150: 300 L6, AOD, RWD. EEC IV / TFI, Feedback Carter YFA Carb. Stock everything but radio (for now).

85lebaront2

Re: Lugging at speed/No power at WOT

Administrator

Ok, AOD transmission is a straight through mechanical connection in drive (3rd gear) If it feels like it is lugging, it may well be. From what I remember on my son's 1986 F150 with a 302, it wasn't super happy at 25 in 3rd. Are the transmission shifts very hard (firm) or just a nice solid shift at part throttle? Are they maybe a bit soft, feel like they are slipping particularly into 3 or 4? These transmissions are super sensitive to throttle cable adjustments, not the one to the carburetor, but the one to the transmission.

I know these were only used briefly on the six due to it's torque, the later trucks actually got the E4OD on everything except the 302. Some 302s had E4ODs, notably 4WD models.

Bill AKA "LOBO" Profile

ratdude747

Re: Lugging at speed/No power at WOT

The shifting isn't particularly harsh, but not particularly soft either. Maybe I need to go tighter on the TV cable?

I tried to get to the idle port to plug in a pressure gauge (Harbor Freight Oil Pressure set) but the cat was in the way and I got tired of fighting with it. Hence why I deferred to the "zero slack" adjustment method.

----

Drove it a bunch this evening, nope, still lugging. It did OK at 65mph sometimes... but other times, as soon as OD kicked in, the speedo dropped like a rock.

Likely unrelated issue: The ignition switch took a shit and nearly stranded me. I knew the accesory position was toast (only works in one exact spot, not the entirety of the detent)... but with key on, backing out of my parents driveway, it jumped to half-start (brake light came on, accessories dropped out), then died. Took a few swipes to get run back... and then I smelled burning electrical stuff. Parked for 5 minutes, tried again, no problems. Was able to get it to act up once I got home... so the contacts are probably toast in there. Toast enough to voltage drop the electrical system into not giving good spark? I doubt it, but at this point anything is fair game.

Still waiting on the TPS to come in. Looks like I'm driving the Ranger tomorrow. Why I have two trucks.

1984 F150: 300 L6, AOD, RWD. EEC IV / TFI, Feedback Carter YFA Carb. Stock everything but radio (for now).

ratdude747

Re: Lugging at speed/No power at WOT

Some quick updates:

-I replaced the TPS... idle got worse. Still lugging. But it did make a difference. I reset the base timing to 10 degrees (as per the indicator) and readjusted the idle fuel with no change either way.
-Yesterday, I power cycled the ECU... and things got way, way worse. Stalled on me several times... and lugged a lot worse than before. I didn't have time to readjust the idle fuel (had to go to Church). Something is very wrong here.

Right now she's out of commission due to a brake line blowing up on my way home. I've pulled the line (rubbed on a frame rivet on one spot, and locally rusted out) and will be bending/flaring it this evening after work.

That said, it seems that something is off. Either I'm not getting good fuel delivery (which makes no sense; no vacuum leaks, rebuilt carb, and adequate fuel supply), or I wonder if I have a mechanical problem (low compression, bad valve timing/adjustment, etc.). My next move will probably be to obtain a compression tester and see what I'm getting there.

Thoughts?

1984 F150: 300 L6, AOD, RWD. EEC IV / TFI, Feedback Carter YFA Carb. Stock everything but radio (for now).

Gary Lewis

Re: Lugging at speed/No power at WOT

Administrator

I'm not buying that you have a mechanical or a fuel problem if things got worse with a new TPS, and then got "way, way worse" with a power cycle of the ECU. That says "electrical" to me. Neither of those changes would alter either a mechanical or fuel problem, and yet they altered the symptoms.

I'd pull the codes now and see what you have. But my worry is that the ECU is bad and, if so, won't tell the truth about codes.

Wait - let me rethink this. You have what I think is an EEC-III system. Wikipedia describes the system this way, and while I don't buy everything else they say about the system, I think this is correct for your application:

EEC-III uses a Duraspark III module (brown grommet where wires emerge) and a Duraspark II ignition coil. A resistance wire is used in the primary circuit. The distributors in EEC-III (and later) systems eliminate conventional mechanical and vacuum advance mechanisms. All timing is controlled by the engine computer, which is capable of firing the spark plug at any point within a 50-degree range depending on calibration. This increased spark capability requires greater separation of adjacent distributor cap electrodes to prevent cross-fire, resulting in a large-diameter distributor cap.

So, I'm guessing that your ignition is "off". Maybe too early. Maybe all over the map. But, it is also very possible that your harmonic balancer has slipped and you are adjusting the timing completely wrong.

I'd start by verifying the balancer's mark to TDC. Get a cheap piston stop that goes in the spark plug hole and gently run #1 piston against it and adjust the stop so that you are stopping just a few degrees ahead and behind TDC. True TDC will be half way between the two stops.

If that is correct, then put a timing light on it and watch the timing as you rev the engine. Does it stay the same? Does it move smoothly? Is it erratic?

Gary, AKA "Gary fellow": Profile

Dorsai

Re: Lugging at speed/No power at WOT

Gary Lewis wrote

So, I'm guessing that your ignition is "off". Maybe too early. Maybe all over the map. But, it is also very possible that your harmonic balancer has slipped and you are adjusting the timing completely wrong.

Wouldn't this be a good time to try vacuum timing the engine instead? Regardless of whether his balancer is slipped or not, he could at least getting the engine running the best it can at idle, and proceed from there.

Gary, AKA "Gary fellow"

I just noticed this!

Matthew
1980 F-150 Custom 2wd longbed, 300-6, C6, 2.75 rear axle
Atlanta GA

Gary Lewis

Re: Lugging at speed/No power at WOT

Administrator

Matthew - Better late than never.

Please show your grandmother.

And tell your mother I'll catch her, age wise, next June - for a few months.

Anyway, yes it might be a good time to set the timing via a vacuum gauge.

Gary, AKA "Gary fellow": Profile

ratdude747

Re: Lugging at speed/No power at WOT

In reply to this post by Gary Lewis

It is not DSII or EEC III.

It is EEC IV with TFI. 1984 was the first year for it on the F series, some sedans got it for 1983. The ways to tell are (1) it has an EEC IV connector and (2) it has TFI ignition (ignition module on the side of the distributor, "narrow" distributor diameter).

The reason I suspect it's a mechanical/fuel issue is that various kludges and the like being removed, which bring the system closer to "stock operation", make it worse. The only sensors I haven't messed (found to be suspect and replaced) with are the MAP sensor (no code thrown, maybe I should test?) and the coolant temp sensor... which I don't suspect due to there not being a code set and my issues not going away with engine warmup/cooldown. I could look there (and probably will, come to think of it), but barring a fried ECU (which is possible but, honestly, remote), I'm running out of electrical control issues to find. The TFI module is new (old one burnt and incorrect module), and I verified that the SPOUT signal is making to said module (10 degree ignition advance from base timing at idle when SPOUT is connected).

Writing this reminded me of two sensors I didn't test... while they're not throwing faults, maybe something is up. Dunno. Will have to test.

1984 F150: 300 L6, AOD, RWD. EEC IV / TFI, Feedback Carter YFA Carb. Stock everything but radio (for now).

ratdude747

Re: Lugging at speed/No power at WOT

In reply to this post by Gary Lewis

I tried vacuum timing it. Brought me to 30 degrees advanced base (stock is 10). Which caused an idle issue (light pinging) once I reconnected SPOUT. When backed off to 20 degrees it stopped pinging but the performance wasn't any better... leading me to believe such isn't the issue.

What I haven't tried (and maybe need to try) is having my wife rev it and see if my timing adjust actually advances. I know the signal is making it to the TFI module (and such is responding), but I don't know if it's actually changing dynamically. Edit- Gary already suggested it that. I need to learn to not read and reply when I just got out of a stressful meeting at work.

1984 F150: 300 L6, AOD, RWD. EEC IV / TFI, Feedback Carter YFA Carb. Stock everything but radio (for now).

Gary Lewis

Re: Lugging at speed/No power at WOT

Administrator

Yes, you've told me before that it is EEC-IV, but I forgot. Sorry. However, if you'd put that in your sig then I should see it before replying next time.

Anyway, I do think you should check the timing with the timing light when the computer is controlling it. And, since you have an auto you can put it in gear, chock the wheels, and put the e-brake on and do a load test.

Gary, AKA "Gary fellow": Profile

ratdude747

Re: Lugging at speed/No power at WOT

Fixed the brake line this evening. Took for a test drive, then did the idle/rev timing light check. No timing change at low throttle, but around 2000RPM or so it jumped to 30 degrees advanced.

It is advancing... but not immediatly.

I took some video of the test drive (of the lugging/stumbling condition)... I'll see if it turned out and if so, I'll post a link.

1984 F150: 300 L6, AOD, RWD. EEC IV / TFI, Feedback Carter YFA Carb. Stock everything but radio (for now).

ratdude747

Re: Lugging at speed/No power at WOT

Yesterday I remembered that the ignition coil was iffy (very loose on core, cracked plastic)... so, as a matter of good practice, I replaced it, and... no change. It needed replaced anyway at least.

Pulled running codes, Codes 41 and 63 Set. The former is the "always lean" code, the latter is a "TPS below minimum threshold" fault.

My next move will be to verify that I'm getting good voltage readings from the TPS at the pin at the ECU connector in the dash... if so, something has gone wonky in the ECU and I'll be cracking it open (I do electronic repair as another hobby, maybe it's something simple blown). If not, I get to trace wires. Fun.

As for the "always lean"... I think that's a symptom, not the root issue. TPS too low -> ECU keeps the mix too lean -> O2 reads lean. Right???

1984 F150: 300 L6, AOD, RWD. EEC IV / TFI, Feedback Carter YFA Carb. Stock everything but radio (for now).

Gary Lewis

Re: Lugging at speed/No power at WOT

Administrator

Yes, I think you are right in planning to test the TPS voltage at the ECU. But I'm not sure there's much to fix inside there. We may have to figure out the part number of that ECU and what other vehicles it was used on.

As for the codes, I don't know. But if you have a new TPS and it still has its knickers in a twist about TPS values then I'd focus on that and hope the lean problem goes away when the TPS issue is fixed.

Gary, AKA "Gary fellow": Profile

ratdude747

Re: Lugging at speed/No power at WOT

Finally had time to crack open the ECU.

No obvious internal issues. All electrolytic capacitors still read good (surprising, given the age of the vehicle). No cracked solder joints or blown components (aside from a diode that the original assembler scarred when hand soldering the ground plate- it measured OK)

I then plugged it back in with the cover off and traced the signal all the way to the microcontroller chip itself. No issues... the voltage was a bit off though (0.8V at idle, 3.8 full throttle). Maybe it is legitimately out of range, but not by much.

Back together... Sometimes connections also go flakey and cause issues, so there is a small chance that with a replug it will start working again. Dunno.

Side note: unlike EFI, these feedback carbs will run without an ECU... not run well, obviously. Maybe the only benefit over EFI?

1984 F150: 300 L6, AOD, RWD. EEC IV / TFI, Feedback Carter YFA Carb. Stock everything but radio (for now).

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