supercharged 5.0 true fire 98 explorer sport

4pointslow · May 9, 2015

Cam timing

Then if that is where it was when it was running good before the second thrust bearing failure, and it is set up the same way now, then the cam timing is not the problem.

So if cam timing is ok, and there are no vacuum leaks (internal or external),
the brake booster doesn't work, and you only have 3 inches of vacuum (even with the brake booster hose pinched off), the only other thing I could think of is an exhaust restriction. Did someone put bananas or potatoes in your tailpipes? How about animals crawling up in there? Neighbors kid put some toys there?

Or maybe the vacuum gauge is bad, and the brake booster is bad too? (two things bad at once)

4pointslow · May 9, 2015

Brake Booster

Did you change the vacuum routing from when it was running good before the second thrust bearing failure?

I see you have the brake booster on the same vacuum tap as the PCV.
The PCV should be separate from all other things that need vacuum, the PCV is a metered vacuum leak so the vacuum on that hose will be lower than others. If it is connected with the brake booster the brake booster may not work so well. And you could have a bad vacuum gauge which would explain the 3 inches of vacuum showing.

vroomzoomboom · May 10, 2015

your not going to believe this.....
today i finished putting everything back together (even contemplated doing it because i was one step away from yanking the motor) and started it up, once again little to no vacuum. so far i have stumped 3 mechanics, 2 auto instructors, and 1 race car/engine builder with this (and anyone here as well). it was getting real low on gas, so i figured the gas station is 3 blocks from me, i will limp it down there and back home. start it up, push the brake peddle, and had power brakes. this didnt surprise me at all because you normally got one pump and they were gone. as i was backing out of my driveway, i stood on the brake peddle knowing i wouldnt have power brakes anymore.....they were there....:scratch:
got on the street, stopped to put it in gear...power brakes....
go down the street get to the stop sign...power brakes...
get going at speed, and hammer the brake peddle....power brakes....
but only 3-5 inches of vacuum. now looking back at things i had to take the boost gauge out when i put my oil pressure gauge in, and that was before i started the motor. when i went to tighten the line for the boost gauge it went out of wack, and had to find the sweet spot for it to read back at zero. thinking of this, and what is going on now i think i fubar'd the gauge and have spent the last week and what ever chasing a problem when all along i may have a bad boost gauge now....
please shoot me... :shoot:

Turdle · May 11, 2015

I know there was a lot of extra work involved, but still you should be happy it is a gauge, and not an internal problem.

4pointslow · May 11, 2015

All fixed!

Glad the power brakes are working now! This is a good sign.

If the boost/vacuum gauge is bad
We were not stumped. You were giving bad data due to a non functional vacuum gauge. I think I mentioned the possibility of a bad vacuum gauge on the phone and the two previous posts. lol.

All ball busting aside I hope to see this thing up and running and setting some new records for fast Explorers!

The last datalog you sent was still running rich(pcm was removing approximately 20% fuel), you need to get the tune going and change that oil right away. There is bound to be lots of gas in the oil and you do not want it to ruin the bearings in the engine.

Also the pcv will be sucking air from the crankcase, if there is fuel in there it will run rich and the tune will be off.

And as long as the truck is running rich from the tune you should only run it long enough to get a datalog, then wait for the next tune until it is straightened out. If you go joy riding it all over with a rich mixture you can end up contaminating the oil again.

1. Change the oil
2. get datalog and send to James
3. wait for next tune

vroomzoomboom · May 11, 2015

oh yea, i dumped the oil out of it yesterday. i had it running long enough (at idle) to burp the cooling system and get gas for it. i may still have it tuned locally for the reason that there is now too much stuff done to it for a remote tune, the shop i may take it to is a sct dealer and does there tuning with the dyno, and my buddy gord that pained it for me knows the owner really good.
also in frustration i did try to bang the throttle once or twice, and she didnt want to have any part of that.

delexploder · May 11, 2015

Great news! Dont feel bad my buddies all joke with me that I should put my rigs together with buttons and zippers cause of how often I have had them apart

4pointslow · May 11, 2015

spark plugs

Check them spark plugs too, you want to make sure the porcelain tip is not coated with fuel/carbon before tuning.

vroomzoomboom · May 11, 2015

4pointslow said:
Check them spark plugs too, you want to make sure the porcelain tip is not coated with fuel/carbon before tuning.

now that you mention that.....new ones coming...
i had to go for a doctors appointment and on the way back was the shop i was talking about that can tune with sct. i stopped in and talked to him for a bit. his pricing is the same as james (and i am not knocking him at all). i think i will get the local shop to do the tune just because he is down the road 20mins away and can dyno it as well.

vroomzoomboom · May 12, 2015

so in the back of my mind i still have doubts at the gauge being wrong (hey, nothing up to this has been easy, why would that be as simple) and i called ford strokers today and talked to woody (he remembered me, so i dont know if thats good or bad). i told him about the problem i was having, and what i have done to check it. first thing he said was its not the cam. his reason was there are thousands, if not millions of cars out the with a retarded timed cam and they all have vacuum, and told me to look at the intake. when i get it running again, i am putting a real vacuum gauge on it, and if it doesnt look right off comes the blower (its not to hard to get it off, maybe 45mins) and i am going to bolt everything to my 302 and look for any cracks on the mount. if i cant find any, off comes the lower intake. what the hell, i have torn everything else off already, might as well do that.....
and when i say when it running again, thats because i have returned it to stock and handed the sct over to the local shop. he is going to write a program for me in the next few days so i can start tuning it.

4pointslow · May 12, 2015

Vacuum gauges

For diagnostic testing I recommend MightyVac or Snap-On for accuracy.

Let the tuning begin!

Dono · May 13, 2015

I agree. Everything has been ruled out but the most obvious. My money is on the upper intake. Welding and flexing of that plate steel......i still don't get why either (starter fluid) doesn't bring idle up. A smoke machine might work in a closed in shop..... your driveway doesn't count.

This has to be an easy solution. They all are once you find the answer. Then its the face palm.

vroomzoomboom · May 13, 2015

speaking of smoke machine, member [MENTION=273315]mikesfiero[/MENTION] had sent a email to me. he had to make one a while back and to me it is pure genius. here is what he sent
"When I installed my M112, I was getting codes 0171 and 0174. This indicated a vacuum leak. I tried searching for it using a gauge then carb cleaner to no avail. I then built my own intake smoker. It was just a paint can with an air fitting on the side and a 3/8 barbed fitting in the lid. I lit some charcoal briquettes and once they were hot dumped them in the can. Then i poured baby oil on the coals and quickly shut the lid. You hook up a length of hose from the lid to a vaccine port on the back of the supercharger. I used the pcv fitting. You ad air to the paint can through a reg. just enough to start the smoke flow. 2psi roughly. Any vacuum leaks start to smoke almost immediately. A bright flashlight helps find the smoke as seen in the pics below. Mine was leaking from under the supercharger, the throttle body gasket, and out of one port on my lower intake. I can't believe how easy it was and how well it worked."

Turdle · May 13, 2015

Iddunno but that has to be about the purtiest IAC valve I have seen.

Dono · May 13, 2015

That is pretty awesome (both the smoker and the workmanship shown in the pics).

So Tim? Are you going to make one?

4pointslow · May 13, 2015

No Indication of a vacuum leak

In SCT's Live Link:
When LTFT is below 1 then the pcm is removing fuel
When STFT is over 1 then the PCM is removing fuel
In Tim's first datalog picture
LTFT .750 is actually removing 25% fuel
STFT 1.30 was actually removing 30% fuel
Total 55% fuel being removed due to the wrong injector data, Tim put 60lb injectors in.
He used to have 42 lb ones If I recall correctly
55% is probably total max fuel trim adjustment with Tim's PCM strategy

In the second datalog picture, with the correct injector data in his tune
LTFT was 1 which means no correction.
STFT was 1.18 and 1.25 which means removing fuel 18% and 25%
That was lots lower than when the wrong injector data was in the PCM, but still rich.
The fuel pressure may have to be lowered and/or the MAF transfer function adjusted.
Anyone still think there was a vacuum leak?
A vacuum leak would be lean at Idle and not as bad at higher rpms.

Note:
SCT makes Fuel trims backwards of each other for some reason.
On a normal scan tool you would see 20% if fuel was being added
and -20% if fuel was being subtracted.... on both STFT and LTFT.
The number 20 is just an example.

Dono · May 13, 2015

I don't know how you keep all this stuff straight in your head.
This is all great news, and back to the boost/vac gauge supplying incorrect data.

I still keep listening to the news expecting to hear there was a vehicle fire in Selkirk Manitoba. Nothing yet. Persistence wins the race.

vroomzoomboom · May 13, 2015

Dono said:
I don't know how you keep all this stuff straight in your head.
This is all great news, and back to the boost/vac gauge supplying incorrect data.

I still keep listening to the news expecting to hear there was a vehicle fire in Selkirk Manitoba. Nothing yet.

...yet...

john, would that should anything if it was a internal vacuum leak however?

4pointslow · May 13, 2015

Internal vacuum leak

Good question,
If you have a closed PCV system (draws fresh air from after the maf), then an internal vacuum leak might not cause a lean condition since the air would be metered by the maf, and fuel would be added during injector pulse width calculations in the PCM.

If you had the PCV system taking fresh air through an open filter on the valve cover it would go lean due to unmetered air.

You stated that you pulled the pcv valve out of the lower intake and felt the hole and there was no vacuum in the crankcase, so that would mean no internal vacuum leak.

vroomzoomboom · May 13, 2015

i run 2 of them. i have one in the passengers valve cover and it goes into the intake between the maf and throttle body, then i have the one in the stock location that is in the lower intake and is drawn into the back of the supercharger.

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