Problem solved!! was :Idle and surging problems

broncman

Registered User
Hello all,
A little info first, new to SC's but not injected fords. I am putting a SC motor in a competition rock craleing buggy for a guy here on the board. Motor was delivered and we got it wired up and running. I am having several problems that leave me bit puzzled.

1. It runs wide open throttle great! or even part throttle. It surges at idle and wants to "hunt for the right idle"?? This motor has no egr and I have insured no vacuum leaks. fixed the ones I found.
I replaced the Idle Air Control valve since this is usually what fixes the problem on most fuely fords. If I allow the throttle to close slowly it will set and idle, but blip the throttle and it stalls when throttle closes adn then stumbles.
2. It drags when starting sometimes like timing is advanced to much on a normal 5.0. Will then start with a backfire and run fine besides the idle problem.

Do I need a new cam position sensor?? I also put a new MAF on it and it made no difference, new O2 sensors as well.
How do I know the cam position sensor is set right? It runs great when your are giving it gas.

Thanks for any advice...
 
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No replies?? well here is more. Codes 82 and 85 on the KOEO. Where is the boost solenoid located?? My factory prints says that it goes to pin 38 on the EEC (89 model). The probst manual lists 38 as SPOUT???? Believe the probst is wrong on that??
What can anyone tell me about the bosst solenoid?

Let it run at idle from cold start without ever touching gas. It took a few cranks and died a few times but I never touched the gas. It finally took off and ran fine for 10 minutes (I even looked at my watch to make sure). Hopefully this gave the computer time to adjust. I then drove it and it worked great till it warmed up driving for about 5 minutes then it was like the timing was too advanced and the hard starts and idle problem came back.
Got to find more about this boost solenoid and check cam sensor.

Anyone?????????
 
Sounds like you are sucking air in a Intercooler tube some were?? And do you have all the ground straps hooked up?
 
Surging at idle is almost always a rich condition. Most often caused by orientation of the MAF or filter design/location. However, in light of your other problems...

regarding the cam sensor, it is adusted by turning it. To me it sounds like it has been turned. This does not affect ignition timing, instead it affects fuel delivery and will cause hard starting conditions such as you described. Could also cause the surging that you are experiencing.

The proper setting procedure is easy. There is a large notch in the balancer. Line this notch up with the pointer on the timing cover such that the motor has just passed TDC compression. This is 26 deg ATDC.

With the HB in that position, remove the cam sensor from the stator housing. Note the orientation of the vane. The solid half should be back towards the motor and when a straight edge is placed across the half moon it should point out directly down the middle of the notch in the housing. Turn the stator housing if necessary.

That's all there is to it.

Don't worry about the boost solenoid. You don't need it and the EEC won't miss it if it isn't there.

The 2 codes you got are for the cannister purge and EGR both of which I'm sure you don't have but will cause a never ending CEL. You can plug the solenoid and sensor back in and tuck them away somewhere. That will turn off the codes.
 
Thanks Dave,
Ken, Dave is the guy that lent us the electrical schematics we are using (They have been a lifesaver Dave. We are taking good care of them and will be returning them soon).

Can you show me where the timing cover you are talking about is?
We are not running that plastic shroud with the timing marks on it.

p1010891.jpg


Here's a couple of pics of what we are working on:

p1010895.jpg


p1010896.jpg


p1010901.jpg
 
Thanks :)
It will be once we get the idle fixed.
Wish I could find someone with a magic wrench to fix it before friday (our first race).
 
Thanks guys for the info. The books I have list the codes as canister purge and boost solenoid. I believe those will be ok.

More tuning... I let the motor idle from cold start for about 10 minutes, never touched the gas at all. I had to crank it a few times at first but it finally ran for the full 10 minutes. I believe this helped the computer learn the idle characteristics. I drove it and it was great for about 10 more minutes till it got to operating temp, then if I killed the engine, it was hard to crank.

Starter dragging like a motor that has to much advance, you know start easy cold but when hot it does not want to turn over as easy. I hope the idle stuff is good now and this was a compound problem. But what would make it hard to start and crank when hot besides timing???

Ken
 
ITS ALIVE ! IT"S ALIVE!!

Popped the cap on the cam sensor after getting to 26 degrees ATDC and the problem was apparent! It was off by about 15 degrees. The guy that built it borrowed the proper tool for alignment , came over and helped me align it. Idle was rough for a few minutes i gues while it probably had to relearn, let it run for 10 minutes and then went and played!! Started fine after it got warmed up and seems like it ran better the longer I ran it!! It also seemed to run a little cooler.
Ken
 
Awesome! Buggy looks sick. I have a question though, pardon my ignorance of rock crawling, but other than the "neat" factor, is there any real reason for using the SC motor instead of an N/A V6 or a V8? Just curious what your reasoning was.
 
A friend of ours had one with a SC motor and that is where AlanSou got the bug. It was fun to drive. I run a standard 5.0 in my rig and a lot of rockcrawlers in comps run vortec 4.3's, Shortstars and turbo'ed EcoTecs. Being the diehard blue oval guys we are , it had to be a Ford. My other engine I want to play with someday is a Turbo'd 2.3. I had an SVO and LOVED it.

As far as this motor goes, it is coupled up to a C-4 with a 9" stall convertor. We run hydrostatic fluid from......John Deere! It is for wet clutches, has higher antifoaming and MUCH higher temp ratings than standard Mercon or type F. This is the tightest auto I have pulled the trigger on. The hydrostatic stuff is going into my rig now!!
 
The bottom end torque of the SC motor has GOT TO be great for rock crawlin.

What gears are ya runnin in that little monster?
 
It is the same reason the 4.0 has been such a great engine in the Jeeps. Lots of torque. The 4.0 makes something like 80% of it's usable torque at idle. I'm guessing 4.88's on the gears, maybe deeper. Also, what transfer case are you running? crawl ratio?
 
5.3??'s in the r&p (ford 9 inch both front and rear!) and an Atlas t case with 4.13's. Even with the 40 inch tires, it hits on the bottom end like a drag car!
 
Thats awesome. A buddy of mine is running an atlas t-case in his Cherokee. Very nice units.
 
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Got any pictures of your crawler?

alansou said:
Thanks :)
It will be once we get the idle fixed.
Wish I could find someone with a magic wrench to fix it before friday (our first race).
 
Can you show me where the timing cover you are talking about is?
p1010891.jpg


Easy enough. It's that chunk of aluminum behind the wrench in the picture you provided :) (A sort of expensive part if you happen to break it whilst removing).
 
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