Codes/problem Help

SCspeedster

Registered User
I have a problem with my 93' SC and I'm trying to fig. out what the problem is. It seemed like the past month or so the car cuts out for just a split second occasionally while speeding up and building boost. It was not very noticable but bothered me enough to get a code reader (Innova yellow box). I hooked up the scanner, dont remember exactly what codes I got but know it was related to my tps was "under voltage".
Acouple days ago while driving and speeding up my SC cut out again but this time much harder. It basically felt like it ran out of fuel or spark when I hit the gas. It did this everytime I hit the throttle alittle hard, then I decided to go and get a new tps and installed it being I had those codes. After installing the new tps I starting the car and went around the block and I had the exact same problem engine cold or hot.
I had another used cam sensor which I switched but that did not help.
I disconnected the battery for about a hr hoping that would solve the problem. I then drove across the street to the gas station and put fuel in it. I then pulled out of the gas station and gassed it abit hard... BIG NO NO. Problem now got worse, car died now and would not start. I tried about 10 times and then finally started after I turned the ignition off then on again. Limped it home without throttle because if I gassed it, it would die again. The car seems to only restart after dying Only if the ignition gets turned off first, otherwise it will just keep turning over without start. I put the scanner on it again and these are the codes I got.
With engine off codes are 111-10-212.
With engine running (did not tap throttle while testing and not sure if I was suppose to) codes I got are 6-10-538.

Also the car idles perfectly until you hit the throttle then rpms will dump and turn off if gassed to hard.

Can someone please help. Thanks
 
Sounds familiar

My 90 was acting very much like your 93. Many different codes that I was chasing but in the end turned out to be a ground issue at the spout connector located directly behind the DIS module as you're looking at the engine from the front.

Look for a single black wire that has a connection just above the A/C compressor, it had frayed to just a couple of strands and would allow the engine to start and run like yours but under boost when the engine would twist it would loose the

ability to ground.
 
Thanks for your input fstcoup. I rechecked all the wires (atleast from up top) and they all seem good. My motor mounts are new and im sure my motor is not moving more then it should.
I was waiting to get a new genuine Ford cam sensor I ordered in the mail before I went back to the SC and start looking at the prob again. The cam sensor I tried wasn't a Motorcraft and It was used so I wasn't sure if it was even good plus I only like to go with factory parts on my rides, especially electronics on this 1. The new Ford cam sensor I installed yesterday didnt make much difference.
I put the scanner on it again with the car running KOER and got codes 6-10-225. 225 being something related to the knock sensor, so I removed it and it still ran like its cutting out but ran better just driving it around the block. It Idled ok and rpms didnt drop and cut out while gassing the throttle at idle like it did before removing the knock sensor but still cut out driving if I hit the gas more then about 1/2.
Any ideas? Does it sound like the prob is my knock sensor?
The knock sensor is hard to find and I dont want to be replacing expensive obsolete parts for this unless I'm sure.
Also when the car stalls as I described and wont restart because the ignition hasn't been turned off first, my shift light is NOT on while trying to restart. I assume from reading online my Crank sensor is ok then?
Thank you
 
Good evening


Start with the simple Checks such as:

1. The DIS module for old/missing heat sink.

2. The harmonic balancer pulley for missing center bolt or the four outer bolts. Look for a "wobble" at idle.

3. The fuel pressure (key on engine off) and at idle (key on engine on). When was the last time the fuel filter was changed?

4. The DIS harness. Any clearance problems between the supercharger belt and the cam sensor connector? Any exposed wiring at the two DIS connectors?

5. Vacuum leaks ( "Y" PCV Pipe at the passenger side valve cover to the inlet plenum, PCV, PCV hose to intake inlet hose driver side, intercooler tubing).

6. Grounds and or corrosion. Radiator support. Negative battery cable to engine ground. Passenger side engine bay to engine ground. Fuel pump relay.
 
Good evening


Start with the simple Checks such as:

1. The DIS module for old/missing heat sink.

2. The harmonic balancer pulley for missing center bolt or the four outer bolts. Look for a "wobble" at idle.

3. The fuel pressure (key on engine off) and at idle (key on engine on). When was the last time the fuel filter was changed?

4. The DIS harness. Any clearance problems between the supercharger belt and the cam sensor connector? Any exposed wiring at the two DIS connectors?

5. Vacuum leaks ( "Y" PCV Pipe at the passenger side valve cover to the inlet plenum, PCV, PCV hose to intake inlet hose driver side, intercooler tubing).

6. Grounds and or corrosion. Radiator support. Negative battery cable to engine ground. Passenger side engine bay to engine ground. Fuel pump relay.

Hello..
the DIS module I removed before replacing the cam sensors to inspect the heat sink and it looked ok. The DIS module had been changed at some point (not Motorcraft) before I got the car.

The harmonic balancer spins very straight. SO GLAD for that.

Fuel pressure I haven't checked yet, the fuel filter I replaced recently.

The DIS harnesses and all other plugs and harnesses in the engine compartment are very clean.

No vacuum leaks, I checked recently. Car wont start (if stalled) unless ignition gets turned off first then on.

All grounds should be clean and tight, I Recently replaced the radiator and went thru it thoroughly.

Thinking about this prob. I decided I am going to reinstall the knock sensor and replace the DIS Module next. Hopefully that's the prob. and wont hurt to have a spare. I will prob. order 1 tomorrow. Ill update the results when I get and install it.
Thanks
 
It seems you gotten a variety of codes listed throughout your posts. Have you tried clearing the codes and driving to see which ones return?

111 O,C,R System Pass
212 C Loss of TACH input to ECA; SPOUT circuit grounded
538 R Insufficient change in RPM
225 R Knock not sensed during Dynamic Response Test

I'm not aware of any single digit codes, such as 6. Are you certain you're using the code reader correctly? The ones that only beep or flash a light at you can be a bit tricky versus ones that give a digital readout. (Not familiar with code #10 either)

Some of your codes seem like they are associated with not running the dynamic response test correctly. Are you performing this test correctly?

Have you completed your plans as outlined in your last post? If so, how is it running.
 
I'm not aware of any single digit codes, such as 6. (Not familiar with code #10 either)
.

I think 6 means # of cylinders, and 10 is a separation code (111 -10- 212), to let you know the reader is done with one test/step and moving to another and/or done, both courtesy of the reader, vs. Ford OBD codes, ...not sure how you can get a O,C,R pass and still get a C, tho. But yes, seems the test wasn't completely done to code reader's satisfaction (538), otherwise.



>5SpeedRed93

Offhand I'd say there are no actionable codes, so far, unless what you're seeing is a trend and maybe the ECU is failing...?

I would repeat the tests, but this time goose it when you're told to use the throttle...put your foot in it. What you said about starting sounds like a cam sensor fail. If you key off, then try again, the computer will substitute a default value if it doesn't hear from the cam sensor and should fire in at least 3 tries. Pls. resist throwing parts at the problem ;) Be sure to inspect the front harness that includes the cam sensor for damage and/or oil saturation, etc.
 
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After replacing all the parts I described ---cam sensor, tps, knock sensor, ignition module--- the car still runs poorly. I have even replaced those replaced items with the originals that were on the car and it runs the same swapping between those parts. I have checked all wires/harnesses that I can see and they all look fine. The car has a more consistent miss/lag when im test driving it around the block or even at idle. When the prob first started it ran good but bucked under boost. Now it has a Consistent Lag Of Power and almost like its missing. It feels like the fuel pump is bad to me. I dont have a fuel meter to test it but when i press the fuel "schrader valve" looking valve on the fuel rail (car running or not) it squirts fuel weak. Definitely doesn't seem like 33 or 36 psi like its suppose to apparently be.
I went back and put all the original parts back on the car like when it was first bucking and it runs as described now. Big lack of power and almost feels like its missing.

QUESTION PLEASE--
I am going to order a fuel pump in the morning. I know they offer a 190lph and a 255 lph pump. With very minimum mods like mine obviously the 190 lph would be fine. The question i have is: is it ok to get a 255lph fuel pump being I intend to eventually really build up the SC and make it as fast as any of the others. Im prob a good 2 yrs away before I hope to really start modifying this bird but never know being I have some other projects I'm also working on. I may never even build this SC up much faster.
I know these cars have a fuel return, but don't know if there is any disadvantages or if anyone would Not recommend the 255lph and just go to with the 190lph.
Thanks again
 
SC_FPR02.png

The fuel pressure regulator is on the fuel rail, near the back of the driver's side head/IC return - if you pull the black vacuum line off the FPR, do you see any raw fuel?

If so, it's leaking internally...not a good sign - can result in reduced fuel pressure.
 
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I think i have seen the fuel regulator. I thought it was above the intake manifold behind the supercharger. I will go home and check this eve. and check that. So its a black vacuum line on the fuel regulator, pull the vacuum line and check for raw fuel? Ok I will let you know thank you KMT
 
I finally was going to look at that vacuum hose last night but could barely even reach it with my fingers much less feel/smell for raw fuel. Is it easier to reach it by removing the wiper cowl? I was almost considering just ordering the new fuel pump being its a original im sure at 25 yrs old. Which fuel pump should I choose when I do get a new 1 anyways?
Either way now I am concerned/curious about raw fuel being there and would like to check that anyways. What does it mean if there is raw fuel in that regulators vacuum line? And I assume removing that cowl should make it easier to get to that vacuum line? Ill be checking that prob by fri. eve. Thanks again for that info!
 
The fuel pressure regulator sees both fuel and vacuum. They are kept separate by a flexible synthetic rubber diaphragm. The diaphragm moves depending on how much or how little vacuum it sees, which in turn alters the fuel pressure at the fuel injector rail by bleeding off excess fuel that is then returned to the fuel tank.

Raw fuel in that line means the diaphragm in the fuel pressure regulator has cracked/failed/been breached - something not uncommon with old/original/high mileage parts. This results in inaccurate fuel pressures, and/or raw fuel being passed directly into the intake track. Another worthwhile check is to put a pressure gauge on the fuel rail. I'd think it would be easier to perform these checks than it would be to drop the fuel tank and replace the pump, but that's just me.

And yes, removing at least the driver's side cowl (includes both wiper arms, and don't forget the screw underneath that faces front), should allow access. These types of troubleshooting steps are typically done first to avoid guessing and wasting $$ by throwing parts at problems, but if you're the type that loves to jack up the radiator cap and roll a new car underneath it, then be my guest ;)

Good luck.
 
Hello, I took the fpr vacuum hose off last sunday and yup.. smells like raw fuel. Does not look fun to replace :(. Any pointers or ideas on replacing is appreciated
Thanks KMT for letting me know to look at that first.
 
Does not look fun to replace :(. Any pointers or ideas on replacing is appreciated

Get the new one in hand first, so you can learn where the bolts are that hold it onto the fuel rail.

Some owners have managed to remove/replace the FPR by just taking the wipers/cowls out and reaching back behind the lower intercooler tube return plenum - see photo. Allen head bolts, don't recall size. RockAuto shows the MOTORCRAFT CM4764 comes with 3 new bolts.

There is a more involved process floating around that includes removing the supercharger - speak up if you need it.
 
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I'll take a good look at it again as soon as I get rid of this bronchitis I got out of nowhere. Removing the supercharger is easy on this being a 93' there is no egr I've already removed it once before.
I already purchased a new fpr from Napa. $40 and the brand name is "Echlin". I assume it's as good as any.
Please let me know if otherwise, I definately dont want to worry about this again for a long time.
Thanks
 
W/the supercharger & lower IC tube return plenum off, there would be generous room to work. The FPR you bought sounds like a good choice. I trust both the brand and the vendor.

Might be a good chance to do the injectors too if they've been in use for a long time. I waited way too long to do mine.
 
Finally got to that FPR with how busy things have been and replaced it. I was thinking I can get to it easier by only taking off the windshield wipers cowl, windshield wiper motor etc.. rather then the Supercharger. I was wrong, got plenty of more room, but not enough. Atleast as far as taking the 3 bolts holding the FPR in place. Then with all that out I also removed the supercharger and jumped in the engine compartment and replaced it...lol.
Runs like a champ now! Thanks again!
 
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