Issues needing help

SK_BlownThunder

Registered User
Okay, here's the deal... (1990 5-speed SC)
-Stock with mild exhaust mods done between stock manifolds and stock gas tank pipe.

Sitting still, idles fine, but when you punch the pedal to the floor quickly from idle, the car stalls out completely. Sometimes while speeding up like normal on the road, the car will tend to give a "buck" or two like it is misfiring or firing on the wrong cylinder or something. Once in a while, say if you shift from first to second and giving her hard all the way, once in second and stomping the throttle, the car while tend to "moan and groan" like it has no power or something along those lines an will continue to do so until you actually let off and push in the clutch. The only thing is to let off, get the rpm up a bit, then let the clutch back out and it will be fine again. Wierd.

Any advice would be great. It's been doing this ever since I reinstalled the HB and using the Ford magnetic spacer strip for the gap setting on the crank sensor. Is this sounding like a MAF problem or worse?

Thanks in advance. I will look forward to some replies.

Brett
 
My dad and I hooked up the Rotunda Ford computer the first time the car started giving trouble. That was to try and diagnose the problem with starting, where the engine "conks out" after turning over a couple times, or doesn't even fire at all. It still has that problem which is also probably part of this problem too. There is something in there that is causing it to do this, and the computer showed nothing for codes or indicators. (Check Engine light does not come on at all either).

We replaced the crank sensor when I did the harmonic balancer and also replaced the cam sensor, both with new sensor assemblies. What is really bad is when my dad doesn't even know where to look next. I keep bugging him of his Master Ford Automotive Technician status as this is the very first problem with an automobile that he hasn't been able to fix, which makes us all feel a bit down too.

Oh well, keep shooting some suggestions. (We also timed the crank with a timing gun and all seemed good so the HB itself can probably be eliminated. What bugs me is that I bought a new ICM which does not even start the car. It conks it out like the old one, except the old Motorcraft one still starts the car! I got the new one because my Motorcraft one tested bad for high rpms. So far that seems to be where the car runs the best is at hight rpms, so I really don't know what's up with that.

Suggestions, please.

Thanks
 
Where the HG's ever done? What your experiencing is what mine pretty much did when the HG's started going.

Do the test on the coolant to see if any combustion gases etc are present.

Frit
 
Redid the entire motor 30 000 kms ago. HGs and all. Put in Sealed Power brand gaskets all around. Since the motor has been done, the car ran just fine, no problems whatsoever. Only started experiencing these issues since replacing the HB. (Got a used one when redoing the motor, but it busted its ring after 7 000 or so kms.) Got another used one to stick on so maybe it could be an issue with the HB too. (Bent tabs or such) maybe. I often though it could have an issue with running the 87 octane fuel I put through this thing. Sure it says premium only, but the computer is able to retard the timing enough and so far so good no knocking or pinging yet. I have tried running premium 93 for three weeks straight. Still no difference in these issues though. Does the same thing no matter what fuel I use.
 
The Computer will not keep it from detonating under boost. Running 87 without pulling the Octane plug is a sure way to hurt the motor. Have you checked the condion of the plugs?

Dave
 
Big Cat Davo said:
The Computer will not keep it from detonating under boost. Running 87 without pulling the Octane plug is a sure way to hurt the motor. Have you checked the condion of the plugs?

Dave

Agreed...if your going to run 87 octane either pull the octane plug or rig the bypass valve to stay open.

David
 
Check the plug wires. I had the same problem on my '89 when I changed the plugs and not the wires. They looked good, so I didn't bother. Would skip and almost die under WOT.

- Zoran
 
Wouldn't you hear it start to knock or ping as first signs of detonation due to lower octane? I try to run Mohawk/Husky ethanol blended gas at 90 octane as much as I can, but with the price of gas going up, I just thought if it ran good on 87, then I could get a way with it. I figured if it isn't pinging or knocking yet, then it should be good to go. I put in Motorcraft platinum plugs when I did the motor in hopes of never really having to pull the plugs in the life of the car again. I guess it really would not be a bad idea just to take a look anyway. As far as I know too, the wires are still good but I am thinking of putting in better ones anyway.

One more thing, how can I sort of "convert" my stock rear lamps into the later model style that light the entire thing up instead of just the corners?

The input is great. After this weekend I'll get the car in the shop and start giving it a look over. For now, I'll be filling it with 92 premium this week for the 100 footers in Cupar this weekend. I usually try and get higher premium for pushing the car harder at times like this.
 
geigerb said:
One more thing, how can I sort of "convert" my stock rear lamps into the later model style that light the entire thing up instead of just the corners?
You need the tails and decklid from a 92+ car to do that...dont 4get the connectors for the tail leds
 
fuel lines...

Check your fuel lines, they may have gotten pinched or crushed under the car. I had the same type of issues with occassional missing and wanting to stall and it was fuel lines pinched from the muffler shop jacking up the car.
 
The computer....

The PCM cannot pull enough timing to prevent detonation from lower octane. THE MANUFACTURER SAYS YOU MUST RUN PREMIUM FUEL!!! The only way to NOT run premium (which by the way is 91 octane), is to open the bypass valve, pull the blower pulley belt, or don't drive the car.

Unfortunately, the higher gas prices have hit us all hard. The knock sensor will detect knock, and most of the time, the problem is too late.

Don
 
Sounds like you need the fix the more important problems first but for those tail lights you will need a new trunk lid, and all 4 1992 on up tail lights and be able to hook up those LED`s with out reversing polarity.
 
Are the plugs double plats? if they are only single Plats the car will run rough.
I know pulling the plugs is a pain in the rear, but if that it was it takes to get your bird running right then that is what it takes.

Dave
 
lube70 said:
The PCM cannot pull enough timing to prevent detonation from lower octane. THE MANUFACTURER SAYS YOU MUST RUN PREMIUM FUEL!!! The only way to NOT run premium (which by the way is 91 octane), is to open the bypass valve, pull the blower pulley belt, or don't drive the car.

Unfortunately, the higher gas prices have hit us all hard. The knock sensor will detect knock, and most of the time, the problem is too late.

Don

So what is meant by too late? If the car still runs good otherwise, then what may I have already wrecked by running 87 octane?
How do you rig the bypass valve to stay open anyway?
 
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