93 5.0L E4OD shudders before downshifting

93, 5.0L, E4OD w cruise, 160K miles

Problem: The engine starts to bogg down and then it shudders before it downshifts and smooths out. (example, when rpm

ok;

This sounds familiar in a few ways, but past problems I've seen have a combo of different causes & effects with SPOUT connected/disconnected; see below.

Number One is to read Codes (DTCs) again; DIY to save $ and possible guesses by the "techs"

A Self Test for Diagnostic Trouble Codes (DTCs) by BroncoJoe

For Key On Engine Running (KOER) portion, the engine has to be @ normal operating temp.

http://broncozone.com/forums/index.php?sho...amp;#entry74587

And here are those causes and effects;

Intermittent No-Spark: Spark w/SPOUT Connector Un-Plugged, but No-Spark (similar to Hesitation, Stumble, Stall, Miss, No Start, No Spark) w/SPOUT Connected, due to grounded SPOUT wire, etc. (for a Ranger, but similar)

;Note, site won't allow you to return to this page, so open URL in a new Window

Source: by Brian M at asashop.org http://www.asashop.org/autoinc/dec2002/techtotech.cfm

This = to:

Hesitation, Stumble, Stall, Miss, No Start, No Spark and/or Diagnostic Trouble Code (DTC) 211 TSB 95-15-11 for 93-95 (Shorts in Profile Ignition Pickup (PIP) & Spark Output (SPOUT)

Source: by Ford via Steve83 http://www.supermotors.net/vehicles/registry/media/470468

EDIT; added Bold feature to the TSB Title because this has occured in some Broncos & F Series in past few years

After more analysis I think that I have two seperate problems; 1) engine - a slight 'miss' under a load, and 2) transmission shifting issues under a load. I took it to another trans shop today for a second opinion and after a test drive they said they though the torque converter clutch was cracked. The estimated repair cost is going to be about $1800 ($1400 for trans rebuild, $400 for converter clutch and solenoid). Does this sound reasonable? and does anyone know if there are other tests that could be run to confirm that the converter is cracked?

I went to another trans shop today for a second (actually third) opinion and guess what. The trans guy took it for a test drive and just like the others, he heard and felt first hand the bucking and shuddering. During the test drive, he said it felt more like it was being caused by an engine misfire than a trans problem. When we came to a stop at his shop he placed his foot on the brake and slowly rev'ed up the engine. When the engine got to between 1800 and 2000 RPMs it started to misfire (badly). He said that the shifting problem (torque converter dropping out and in of lock-up) is being caused by the misfiring engine. So, out of three trans shops, two say the shifting problem is being caused by a misfiring engine and one says it's a cracked torque converter clutch. One thing I know for sure, with the foot on the brake it starts to misfire at between 1800 and 2000 rpm. When I got home I pulled the codes and I got a 654 (MLPS not indicating park), and 452 (VSS signal small). I'm thinking that the 452 could have been caused by the static rev up. Any ideas on what's causing the misfire will be welcomed.

buck45 said:

I went to another trans shop today for a second (actually third) opinion and guess what. The trans guy took it for a test drive and just like the others, he heard and felt first hand the bucking and shuddering. During the test drive, he said it felt more like it was being caused by an engine misfire than a trans problem. When we came to a stop at his shop he placed his foot on the brake and slowly rev'ed up the engine. When the engine got to between 1800 and 2000 RPMs it started to misfire (badly). He said that the shifting problem (torque converter dropping out and in of lock-up) is being caused by the misfiring engine. So, out of three trans shops, two say the shifting problem is being caused by a misfiring engine and one says it's a cracked torque converter clutch. One thing I know for sure, with the foot on the brake it starts to misfire at between 1800 and 2000 rpm. When I got home I pulled the codes and I got a 654 (MLPS not indicating park), and 452 (VSS signal small). I'm thinking that the 452 could have been caused by the static rev up. Any ideas on what's causing the misfire will be welcomed.

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Good that you got those Codes and the 2 other opinions Buck.

My ISP is giving me fits again here; Comcast just won't admit that they have a conn. problem here in da pines.

Is the PSOM & Cruise working 100%?

So, for now, here are 2 possibilities;

DTC 27, 29, 452, P0502, P0503, PO716, PO718; Insufficient input from VSS.; "...A more difficult problem to identify is a VSS that works, but sends out the wrong signal for a given vehicle speed.

In some cases, a wrong reading from the VSS may still cause a code to be set. For example, if the VSS signal tells the computer the vehicle is traveling 60 miles an hour, but the throttle position sensor and MAP sensor tell the computer that the engine is idling, the computer will be confused. And a confused computer should set any of the following codes: Ford 27, 29, 452. On a vehicle that uses the VSS as a safety device, a defective sensor may send out a wrong "too fast" signal, shutting down fuel flow at the wrong time. Although this doesn

PSOM; The speedometer needle is steady and the stored PSOM settings are 'E 08 6' and '9.18 CAL'. I'm running BFG 32's (calls for 8.87.CAL) but I haven't reset the PSOM. Other than indicating a speed that is slight lower than actual (and miles slightly less than actual), I'm thinking the CAL setting is a probably a non-issue. I've read Steve83's well documented PSOM post, but, unless I find something that points me to a PSOM problem I'm going to assume it's OK. CRUISE CONTROL; It has worked in the past, but, since I haven't used it lately I'll re-check it. Thanks for your input and advice. It looks like I'll have plenty of time to do some reading and research today since it's raining here in the land of the pine. I'll follow-up as things develop.

I replaced the differential speed sensor (on top of the rear differential). I also inspected the connector and wires. The wires were laying on the exhaust pipe! and the wiring enclosure had pulled away from the frame and was rubbing on the front driveshaft. While there was some wear where the wiring was making contact it looks like the wiring is OK. However, I'm still getting 452. I've been told that there may be another sensor, called the 'Vehicle Speed Sensor, that is either mounted ON or IN the transmission. I looked at this other VSS at the parts store and I know what it looks like ,but, I've looked for it on my trans and I have yet to locate it. I've got a 93, 5.0, E4OD with cruise control. In addition to the sensor on the rear differential, do I have a VSS either ON or IN the trans and if so where is it located, and is it something I can replace myself?

buck, ok

You prob got the right VSS; its mtd on the 8.8

Now there is a little BW 1356 Electric Shift Speed Sensor but that is just for the Xfer case operation. So you won't need that

Prior yrs did have the VSS mtd in da transfer case tail housing

Since the PSOM is working "perfectly"

Look @ Steve83's info;

http://www.supermotors.net/registry/media/170517_1

of course, thanks to Comcast, I can't open Steve's SM page now... he has the troubleshooting in there.

He talks about using a Volt-Ohmmeter, by-passing the 4WABS module (not likely since PSOM is working 100%, & differential speed sensor (on top of the rear differential) resistance test (see my above psot about this)

See if your Cruise is workin perfectly now and repot back

If it is working ok... we have a problem in the wiring from PSOM to PCM or possibly a BAD DIODE in the Alternator's Rectifier. Is your alt doing good?

Also, did you get the recall done?

The pin-point testing is the only way to go for these problems.

you'll need a Ford Bronco Electrical and Vacuum Troubleshooting Manual (EVTM), Powertrain Controls and Emission Diagnosis Manual (PCED), Service Manual CD - see Steve83 for best deal.

Alternator OK. I turned the cruise on briefly the other day and it worked but I'll take it on the highway in a little while to give it a more thorough test. I gotten a little side-tracked at the moment because I can't get the KOER test to run. I've tried KOER with two different code readers (Actron CP9015 and Innova Equus 3145). I don't think it's the readers' because I ran the KOER and the cyclinder balance test on my 94 ****** and it worked fine. With the Equus 3145; I start the engine, turn the reader on, toggle from hold to test, and 000 displays (normal). After a few seconds the number of cylinders should display. But it never gets past 000. As I said, it works fine on my 94 ******. So, KOEO works, KOER doesn't work! Buy the way, on KOEO I'm getting a 654 (MLPS not indicating Park position) and I'm wondering if this is keeping the test from working. Any ideas?

Distributor was causing the problem. I finally decided to replace it and now my Bronco's back to normal. No more shuddering! The first trans guy's diagnostic was correct. He ruled out a trans problem and said that the shuddering was caused by the engine misfiring and that the distributor was causing the misfire. He proved his point by disconnecting the SPOUT connector. The problem went away when the SPOUT was disconnected. More than one mechanic ruled out the distributor and told me they suspected trans issues and another trans shop diagnosed it as a cracked torque converter clutch (estimated $1800 cost to repair)! I feel fortunate to have found a trans guy who was also an expert mechanic, otherwise, I would have had the trans rebuilt before finding out that the distributor was actually causing the problem. Now, the defective distributor is on its way to wherever to be rebuilt, sold again, and live another day. Thanks to everyone for your recommendations and guidance.

Glad he found the problem!

Look like that Link I gave ya had some clues in it; did he say it was da PIP?

I know this is an old post but I have been trying for days to figure out a misfire I get when my BKO is warm. 1993 EB 5.0 E4OD. The enhine runs great if you start it amd warm it up and srive it. I can drive it forever but when I shut it off, even for 2 minutes, it misfires. The PO told me when I bought it that it was running lean but I had intended to swap the engine for the one in my wrecked BKO. Problem was, it has 160+ PSI in all of the cylinders and all of the original engine components, including emissions, are intact. I have been through everything I can think of with this BKO except changing the ECU. It does not throw any codes when I test it on the first start when its cold (yes I allow it to come up to temp). But when I retest it, it gives the code for "cylinders out of balance". I guess my question here is if it is misfiring and I pull the spout and it does NOT misfire, are you saying that means the PIP is bad or acting up when hot because I tried that and it didn't misfire with the spout out.If so, how does this explain the lean condition? Thanks for any input here as I have been searching for days to an answer to this dilemma.

MrWP819300 said:

I know this is an old post but I have been trying for days to figure out a misfire I get when my BKO is warm. 1993 EB 5.0 E4OD. The enhine runs great if you start it amd warm it up and srive it. I can drive it forever but when I shut it off, even for 2 minutes, it misfires. The PO told me when I bought it that it was running lean but I had intended to swap the engine for the one in my wrecked BKO. Problem was, it has 160+ PSI in all of the cylinders and all of the original engine components, including emissions, are intact. I have been through everything I can think of with this BKO except changing the ECU. It does not throw any codes when I test it on the first start when its cold (yes I allow it to come up to temp). But when I retest it, it gives the code for "cylinders out of balance". I guess my question here is if it is misfiring and I pull the spout and it does NOT misfire, are you saying that means the PIP is bad or acting up when hot because I tried that and it didn't misfire with the spout out.If so, how does this explain the lean condition? Thanks for any input here as I have been searching for days to an answer to this dilemma.

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yo,

re; and I pull the spout and it does NOT misfire,

I'm going w/PIP/& OR a Magnetized Shutter Wheel

Misfiring, Rough Idle, Surge, & Ping-Knock Symptoms, due to a Magnetized Shutter Wheel, (Bronco & all Fords w/EEC IV & TFI); "...Inside the TFI distributor is a Hall-Effect sensor that provides an RPM and POSITION signal to the Ignition module and ECM for fuel and ignition control. Mounted to the distributor shaft is a "shutter-wheel" that passes through the Hall-Effect sensor. The slots or windows cut in the shutter-wheel are what makes the Hall-Effect sensor switch on/off to create the signal it sends out. The shutter-wheel is supposed to be a piece of "dead" steel but can become magnetized. A magnetized wheel can cause very erratic operation of the Hall-Effect and resulting erratic output signal. The Test: There are a couple of ways to check for this condition. One is to simply pull off the distributor cap and see if something steel will "stick" to the shutter-wheel. Make sure that whatever you are using to check the wheel with isn't magnetized itself. A more accurate method would be to watch the wave-form on the "SPOUT" wire with a Vantage or Lab-Scope. The SPOUT is the wire with the connector in it that you unplug to set ignition timing. Monitor the wave-pattern on the SPOUT with the timing-connector in. If there is anything erratic about the wave-form, unplug the timing connector and re-check the wave-form. If the pattern "cleans up" all of a sudden, chances are good that you have a magnetized shutter-wheel. The Fix: Most shutter-wheels can be removed from the distributor shaft with a couple of screws. Everybody seems to have their own way of de-magnetizing the wheels but good success has been had with bulk audio-tape erasers or by placing the wheel in an engine parts cleaning oven and baking it. That last one sounds weird but it works..." Scroll down

Source: by snapon.com via archive.org @ Misfiring, Rough Idle, Surge, & Ping-Knock Symptoms, due to a Magnetized Shutter Wheel, (Bronco & all Fords w/EEC IV & TFI); "...Inside the TFI distributor is a Hall-Effect sensor that provides an RPM and POSITION signal to the Ignition module and ECM for fuel and ignition control. Mounted to the distributor shaft is a "shutter-wheel" that passes through the Hall-Effect sensor. The slots or windows cut in the shutter-wheel are what makes the Hall-Effect sensor switch on/off to create the signal it sends out. The shutter-wheel is supposed to be a piece of "dead" steel but can become magnetized. A magnetized wheel can cause very erratic operation of the Hall-Effect and resulting erratic output signal. The Test: There are a couple of ways to check for this condition. One is to simply pull off the distributor cap and see if something steel will "stick" to the shutter-wheel. Make sure that whatever you are using to check the wheel with isn't magnetized itself. A more accurate method would be to watch the wave-form on the "SPOUT" wire with a Vantage or Lab-Scope. The SPOUT is the wire with the connector in it that you unplug to set ignition timing. Monitor the wave-pattern on the SPOUT with the timing-connector in. If there is anything erratic about the wave-form, unplug the timing connector and re-check the wave-form. If the pattern "cleans up" all of a sudden, chances are good that you have a magnetized shutter-wheel. The Fix: Most shutter-wheels can be removed from the distributor shaft with a couple of screws. Everybody seems to have their own way of de-magnetizing the wheels but good success has been had with bulk audio-tape erasers or by placing the wheel in an engine parts cleaning oven and baking it. That last one sounds weird but it works..." Scroll down

Source: by snapon.com via archive.org

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Next is; did you get this Code 538 Invalid cylinder balance test due to throttle movement during test?

If so, then all is ok bec throttle was pressed/moved during self test.

If it's another code, then *** the Code here or look it up in my broncolinks.com site and type just the code number in the Search feature.