View Full Version : Another ignition issue for the SC experts....

fomoco man
10-20-2005, 03:30 PM
O.K., So I just got through reading the thread on the "Coil-Pack won't fire".

I'm a little old school and new to troubleshooting SC problems. I have a similar situation to the previously-mentioned thread.

Here's the story: '92 SC stick car. No mods except K&N. Mileage 140,000. With exception of air filter, tires, brakes, and battery, COMPLETELY original. In the past week or two, it started "hiccuping" while going down the road. It would signal a "check engine" light on occasion, but when I had the codes run, nothing comes up. It has never failed to start, until three days ago. I remembered a similar "hiccuping" problem I had on a Ranger 10 years ago which I solved with an ignition module. So, I purchased a DIS ignition module and installed it last night (with dielectric grease of course). She will crank forever (recent battery), but still won't start. Haven't put a gauge on the fuel rail yet, but it sounds like the pump is coming on and pressuring up the rail like normal (another lesson learned on an '89 SC years ago).

I haven't been "into it" yet, but was hoping to hear more on the "cam sensor" and the "crank sensor". Also, the physical locations of each. Is one of these fed off the DIS passenger-side pigtail plug-in? There are two connectors up there near the module and its two plugs. Also, how you you check out the coil pack? Likewise, is there a tell-tale sign to look for when the balancer starts to go south? I've never really traced the underhood wiring out, so I'm a bit ignorant when it comes to specific components on an SC.

I was hoping to get some direction from you SC gurus. Any help is appreciated (my little one misses the burnouts in the 'Bird- but the clutch is getting a rest)...

fomoco man

'85 Turbo Coupe 5-spd (best car I ever owned- 191K)
'88 Turbo Coupe AT (didn't like the slush box effect)
'89 SC 5-spd (a dream on the twisty-curvies, better park it when it snows)
'92 SC 5-spd (present driver, awaiting help in the driveway)

10-20-2005, 04:03 PM
First of all, go get codes pulled. "Coil pack won't fire" Is most definitely the cam sensor. These usually go out at about 80,000 miles or so. Symptoms are that code and sometimes a jumpy tach.

If crank sensor is bad the car wont start and you will know if its the crank sensor if the upshift light turns on while you are cranking the motor over with the starter.

Another thing, you can't use dielectric grease under the DIS module you HAVE to use heat sink compound. You can find this at Radio Shack.

A little back my car sounded like it was running on 4 cylinders, the tach would go all over the place, and sometimes it would run normal for a couple of minutes. I went through all types of parts trying to figure out. I was using dielectric grease so I thought that everything was okay until one day I pulled the DIS, wiped all of the dielectric grease off and put the heat sink compound on and it worked great.

Joisey Jim
10-20-2005, 04:11 PM
Yes, maybe they just ran current CEL codes (KOEO test) and didn't check the stored codes. Not all coil related codes automatically mean a bad cam sensor; generally they would point towards a bad DIS. If you get the Haynes manual it will show you how to test the coil pack - but I bet that is not your problem. On earlier SC's an erratic tach would indicate a bad cam sensor and on later models more likely CEL # 214 .

fomoco man
10-20-2005, 04:45 PM
O.K. It's starting to make a little more sense. At times while cruising down the road, my tach will immediately jump up to 4000 rpm, sit there for a while, and then drop back to normal. So this is an indication that the cam sensor is going out? Where is the cam sensor located?

Also, when I bought the new DIS module, it did not come with any gel for the backside. When I asked the parts guy at the counter (Advance replacement part- couldn't score a FORD module anywhere) he told me to "use this". Thus the dielectric grease.

10-20-2005, 06:05 PM
Just trust me on this. You can't believe people at a parts store over SCCOA people, come on :D . I thought dielectric grease would work, but it didn't. It's cheap stuff so might as well try it.

DIS module can make the tach jump too.

fomoco man
10-24-2005, 04:28 PM
Update from the weekend work on the '92 SC:
New DIS module pulled off and cleaned of dielectric grease.

Heat-sink compound (Radio Shack knew about it and supplied it) put back on.

Crank, crank, crank. Still nothing.

Cam sensor located and replaced.

Crank, crank, crank. Still nothing.

Still no CEL and still not running.

Any ideas???

10-24-2005, 04:51 PM
How many times have you tried to crank it over? Is it possible your battery could be low by now after trying and trying? I remember that happened to me once in another car that i had. I had something go wrong with it and let it sit for like 4 months and when i went back to it, fixed the problem, and tried to start it, it wouldn't go. All the interior lights worked, the headlights weren't bright, but they worked, so i thought it couldn't be the battery... I got pissed off and gave up, my friend took the battery off and tossed it on the charger while i was inside eating and watching tv. Later that night he's like let's just look at it and give it one last try before you give up on it again, i'm like naa, i dont care anymore, i'll get to it sometime and he went out without me, plugged the charged battery in, turned it over for a few seconds and it fired right up, Which never happened with that car, i mean after all it was a fiero...

10-25-2005, 07:21 AM
The question was asked by CMac89 but never answered. I had a 90 XR7 SC stick. Driving it home after I bought it, the car died. So began the saga of my SC experiences. It would not start and the UPSHIFT light was on as I cranked it. I had no CEL. So I asked my local Ford dealer service manager what he thought the problem was. This guy is good. Right off the top of his head he aked if the upshift llight was on when I cranked it. Yup, sure was. He told me the crank sensor had failed. They normally fail at around 80,000 to 100,000 miles. I replaced the crank sensor and it started right up.

94 Red SC Auto: 70mm TB, Fresh Air Intake, Stock 90 SC Pulley, Accel 36# injectors, Scorpian 1.73 Rockers, ARP Head Studs, 190 l/h fuel pump, 180 Stat, Raised SC Top, I/C Fan, Headers, Raven Muffler (no cats) with stock resonators, 3:73 Gears, 76 C&L MAF (Gold Tube), Magnacore Wires, NGK Iridium Plugs, MSD Ignition, TRANSGO Shift Kit, Haydon Auxiliary Transmission Cooler, ProTorque 2500 TC, Tokico Struts & Shocks, Royal Purple Synthetic Lubricants, Optima Yellow Top Battery, American Racing 17 Sniper Wheels, Michelin Pilot Sport A/S.

fomoco man
10-25-2005, 04:36 PM
First of all, I still have a hot battery in the car, and it spins the engine readily to allow for start-up.

In response to the question on the upshift light, I have to say "no" it never came on. Now, I say this for I have never seen this light "on" in this car ('92 SC-stick) nor in the other car ('89 SC-stick) I used to drive. I guess the bulb could be bad or a poor connection, which in either case, it wouldn't show a light. I assume the light is in the instrument cluster in the same row where the CEL, brakes, and anti-lock lights are located.

Last week after the cam sensor replacement did not solve the problem, I was planning on replacing the crank sensor, but the switch was not available locally and had to be ordered. When discussing the problem with the parts guy, he started talking about computer failure. At that point, I decided to hit the SCCOA site up for help before I kept throwing more money at it doing the guessing game.

Kevin Varnes
10-25-2005, 05:28 PM
The upshift light is amber in color and is on the bottom row of the instrument cluster with all of the other warning lights. It should come on for a second and go out when you turn the key to on. I think it would be pretty hard for the bulb to burn out, but anything is possible. Check that and get back to us. Also, if you can, check the crankshaft dampener while someone turns the engine over. If it wobbles you have one problem. Also check for the center bolt in the dampener that bolts to the crank snout.

Silver R
10-25-2005, 08:38 PM
I've been having the same problem with my 90 SC (auto). I've changed out the Cam Sensor & DIS. Car worked good for about 5 min. and then went dead. I've tried to turn it on for about 3 min. but engine only cranks and doesn't turn on. I did use Heat Sink for the DIS but I still don't know what is going on. I've checked to see if anything is wrong with the balancer but everything is OK. I'm stumped. :confused:

10-25-2005, 09:44 PM
im thinking crank sensor thats about all i ever had problems with

10-25-2005, 10:28 PM
Another vote for the crank sensor.

When they start to go you get the "hiccup" you describe. Let it go a little longer, and you will be driving down the road and the car will just cut out and die on you. You pull to the side of the road, and crank, crank, crank...but nothing.
You wait 20 to 30 minutes and then it fires back up.

fomoco man
10-26-2005, 04:12 PM
As far as the upshift light, I still can't ever remember seeing it lit up. I'll check with a flashlight on the dash warning lights to see where this resides in the cluster.

Yesterday after posting my latest update on my downed 'Bird, I went to the local parts store and ordered a crank sensor. I am picking it up today and hope to get to work on the install this evening. While underneath, I plan to check out the balancer as well as the retaining bolt. I've seen a link on the replacement balancer and also shots of failed units. Hopefully that will not be the problem I am having. I'll post again after the latest part has been installed and tested.

Maybe with a little luck, I'll soon have "the 'Bird flying high again". Thanks again for all the input and suggestions.