My SHO is slow ...

[SHOWYA]

Really slow acceleration until secondary runners kick in then more power like it always is on the SHOs but feels like it looses fuel pressure. I did check for codes on it and i am getting 411,412,511, 157,538
How can i solve these?
Im already going to buy the throttle sensor.

 

[SHOguy 92]

chec sdpatts profile he has links to see what codes mean or u can download the 89-95 SHOshop manual that has what the codes mean and take a look at what u got

 

[revhardSHO]

midwestsho.com has the code library. That should give you some indication of whats up.

 

[BeatDaSHO]

Cannot control RPM during self-test low RPM check.

Cannot control RPM during self-test high RPM check.

EEC processor ROM test failure.

MAF circuit below minimum voltage.

Operator error (dynamic response / cylinder balance tests).


The first two I believe have to do with the IAB valve not functioning properly. Try cleaning it. I'm not sure what to do about the EEC processor ROM test failure. The MAF means that it probably needs cleaning. And the last code means that you didn't do the cylinder balance test so don't worry about that one.

Greg

 

[billyshoe]

All SHO's are slow til'the secondaries open-then there is some improvment. The Ford Taurus is underpowered across the board. Its better(maybe) @ 5000rpm & up-but not good enough. Its a big heavy car.

 

[drivinhard]

The SHO has a dual torque peak, typically the torque at ~2900 rpm is essentially the same as the torque at ~4800 rpm. In a given gear, the car will always accelerate hardest in the rpm range where it makes the most torque. Past 5.5k the torque is falling off (with stock cams) and the car is not pulling as hard. Just cuz it's making more noise and vibrating more don't mean it's going faster...

 

[SHOWYA]

billysho,
I know that the SHO is slow to a certain extent. But i have a few upgrades which make it 'feel' alot quicker. Now i dont feel that quickness that it used to have, plus i can totally feel that its hesitant. I did replace the IAB valve not to long ago ... maybe 3Mo. or so. I did the reset procedure for the idle speed. No difference, stll the same.

 

[projectSHO89]

Your Superchip is the cause of the EEC ROM code. Ignore it.

Replace the Idle Speed Control/ Bypass Air (ISC/BPA) valve.

Check the MAF circuit and clean the sensor wires.

Practice running the test, the timing can be tricky until you get the hang of it.

Steve

 

[SHOWYA]

Steve,
Do you mean the timing for leaving it idle 30 sec. then apply the accessory load before 70sec.??

I will get some carb cleaner for the Bypass valve. Whats recommended to clean the the MAF connectors???

 

[billyshoe]

Maybe a rear brake is hanging?

 

[projectSHO89]

I meant your timing as to the execution of the KOER tests.

The MAF sensor wires can be cleaned with electrical contact cleaner or brake parts cleaner.

If you use carb cleaner in the valve, you may melt any plastic parts inside it. You notice that I did not suggest cleaning it.

Steve

 

[SHOguy 92]

billyshoe SHO's are really weak under 4000RPM's its just slow revving it seems to be very slow revving in that range now thats what a light weight flywheel and some lighter rims will imrove im sure that'd make a big diffrence the 8lb fidenza flywheel i hear rocks 3hp more and way faster revving.

 

[SHOWYA]

Steve,
Will a vacuum leak cause that problem with the bypass valve?

 

[SHOWYA]

Also,
I rented a scan tool just to double check my the codes. An im getting 542 and 211. Does do 211 have to do with the crank sensor? (aka PIP sensor?)

 

[billyshoe]

I don't have code info on hand. I can say the PIP is working 100% if the engine runs. If the PIP malfunctions the engine will not run. This does not mean the PIP is good. A faulty PIP will not cause the type of drivability problem you mention other than stalling/no start.

 

[projectSHO89]

SHOWYA:
Steve,
Will a vacuum leak cause that problem with the bypass valve?

The bypass valve is a metered vacuum "leak". If it malfuctions, the computer cannot control the vacuum "leak", resulting in an inability to properly control idle speed and TB airflow relative to throttle plat settings (as read by the TPS).

Steve

 

[SHOWYA]

well replaced bypass valve and TPS sensor. Idles fine now after it warms up. When cold the engine will initialy start idling at around 500RPM then moveup to 900RPM as it warms up and if i hit the gas it will almost die. So im still having the loss of power problem. To give you a more exact idea on how its actually reacting, try to picture it like if you are trying to go from a dead stop in 3rd gear. JUST TAKES FOREVER!

 

[AutoSHO]

MAF sensor. Clean it.

 

[sdpatt]

Have you reset the idle speed since replacing hose components?

 

[Devin]

A couple of points:

When cleaning the MAF, be careful you do not harm the electrodes, otherwise you can ruin your MAF ($130+ new).
Also, I agree with Steve. I had the same two codes you had for the idle problems in my Topaz. It was because of the IAC (Idle Air Control) motor. I got a replacement at a boneyard for about 3 bucks and the car runs like new.

The way I found out mine was bad (besides sympotoms) was that the little rounded fin assembly in the motor was broken and spun freely. You should not be able to spin it yourself.