Surging troubles......

[needragr]

IDLE SPEED CONTROL SYSTEM - Idle speed control by-pass air (ISC-BPA) valve.

1) remove ISC-BPA valve from engine. Connect a hose from a hot water tap to coolant inlet nipple on ISC-BPA valve. Blow through valve air port. Note resistance to airflow.

2) Supply hot water to ISC-BPA valve. Blow through valve again. If resistance to airflow does not increase when valve is hot, replace ISC-BPA valve.

3) Apply 12 volts to solenoid terminals. If solenoid does not click, replace ISC-BPA valve. Measure resistance across IAC teminals. If resistance is not 6-14 ohms, replace ISC-BPA valve.

Per repair manual.

Trouble shooting today I found this post. Found my ISC open but barely. Shot some pb blaster down the bores let it soak a while blew out then did the hot water test. A-OK it closes completely . Tested resistance also ok at 14 ohms & applied 12v to the connector & it does indeed click so its supposed to be good.
But I thought I read this was a stepper motor that incrementally opens or closes? How do you cycle the opening/closing range?
Also what is the test for signal / voltage on the connector from the ECU ? i

[TominMO]

Banned for hijacking thread with items for sale. GLWS BTW.

[FordFestiva]

Previous post was from Mitchell Repair CD set.

I was still experiencing intermittent surging after replacing the coolant temperature sensor.

For future reference, keep an eye on your big rubber tube connecting the VAF to plastic oval intake tube . Mine had started deteriorating (underside - not viewable) and caused excessive air intake past the VAF. I had used a roll of electrical tape to seal. Doesn't look too bad and serves the function, but I would like to replace the rubber tube if possible.

I hope this helps any other party having the same problem.

PS - I still have a few side window wind and rain deflectors for sale if you are interested. $150 for the pair which includes shipping to the contiguous forty-eight states.

Best wishes and take care,
Al from Alsip, IL

[FordFestiva]

IDLE SPEED CONTROL SYSTEM - Idle speed control by-pass air (ISC-BPA) valve.

1) remove ISC-BPA valve from engine. Connect a hose from a hot water tap to coolant inlet nipple on ISC-BPA valve. Blow through valve air port. Note resistance to airflow.

2) Supply hot water to ISC-BPA valve. Blow through valve again. If resistance to airflow does not increase when valve is hot, replace ISC-BPA valve.

3) Apply 12 volts to solenoid terminals. If solenoid does not click, replace ISC-BPA valve. Measure resistance across IAC teminals. If resistance is not 6-14 ohms, replace ISC-BPA valve.

Per repair manual.

[Papabug]

It is fixed.

The IAC is just like an automatic choke. It does nothing once the car is warmed up. But I did replace it with one I found on E-bay. This fixed the problem completely. If you just bypass the IAC you will have a very cold blooded car. I will not like to idle until it has warmed up and if yours is like mine it never really gets very warm in the cold months. Good luck.

[Festiva Time]

So you didn't fix the problem, you just disabled the ISC-BPA.

[Papabug]

John, the vacuum line I plugged is the one that goes to the plenum. I plugged the male part and then put the hose over the plug.
No, i did not replace the O2 sensor. I did replace the TPS this stopped the accelerating to compression problem now runs smooth as a top.
I again would like to thank all the people on this board for the help and patience. This is truly a great board.

[JohnGunn]

Does this thread have a happy ending?

It was like when you backed off the gas the engine would shut off or go to compression until you stepped on the accelerator again. No in between.

Hey, Papabug.

Since my '90 Festiva demonstrates the problem you described in the above quote, I would be extremely interested in hearing how this story ends.

Did you find a replacement Idle Speed Control/Bypass Air(ISC-BPA) module? And, if so, did it correct all you problems?

You also seemed determined to try installing a new Oxygen Sensor to see if that would address your problems. Did you do that and, if so, to what effect?

You said the problem pretty well went away when you plugged one of the vacuum hoses. Exactly which of the four hoses that connect to the module did you block and how did you actually physically accomplish it? I'd like to see how that would affect my problem.

I'll try and PM you in case you have stopped following this thread.

I, for one, will thank you for your trouble.

John

[Papabug]

Hey there again,

Bonus point for mechanicaldj! It is/was the Idle Air Controller. I checked around for one. You can't get the part from anywhere but the Ford Dealer (595$). More than I paid for the whole car. So. I plugged the vacuum line where is enters the TB, kinda cold blooded now but surging is gone and runs better that it ever has, new plugs / cap / rotor probably has something to do with that too.

I have a call in on a 92 that runs and drives whatever that means for, I hope around 250$. Waiting for a call back. Keep your fingers crossed.

Does anyone have one of these items they would like to sell?

Thanks

[Papabug]

Ok, I have done the plugs, rotor, dis cap and Seafoam, no change does seem to run a little better but the up and down idle is the same. Another thing I may not have mentioned. It seems that as long as you are accelerating it is fine but when you lift your foot from the gas pedal to hold a constant speed it's like the engine shuts down or goes to compression seems there is no cruising it's either on the gas or off no in between.

I found this on another post:
check your fuel regulator it is located on fuel rail near fuel pump remove black vacum line with green marks it goes from regulator to throttle body remove it from throttle body end now suck on it and it should hold vacuum with your tongue. if not replace . if it does not leak do this.. plug open fitting on throttle body and start car if you suck and blow on hose going to reg. engine should change speed and stumble as fuel press fluctuates if not replace reg they are cheap.

I did as advised and seems that it is not responding as the poster said it should. Blow/suck no change. I tried to get the thing off but the bolt that is under the intake is impossible to remove it seems with out dissembling the intake. Or or there a secret to getting this bolt out? Are there other tests for the fuel regulator? I'm not too crazy about removing the intake if I don't have to. This is on a 1991 EFI Festiva.

Thanks
Papabug

[Papabug]

Here's the plan

Went to the auto parts store bought new plugs, cap and rotor and a can of seafoam. Gonna replace the above and do the Seafoam treatment tomorrow. Will post the results.

I thank you guyZ for all the assistance.
Papabug

[Papabug]

Auto Zone (nope)

I think it may be a universal motor, but I'm not sure... here is a different link:

http://www.autozone.com/autozone/cat...ey+Performance

I don't think that will work, doesn't look at all like the part I have.

Thanks for taking the time to look it up.
Papabug

[doylerl]

I think it may be a universal motor, but I'm not sure... here is a different link:

http://www.autozone.com/autozone/catalog/accessories/accProductDetails.jsp?categoryDisplayName=Performance&fromString=search&itemIdentifier=114309_0_0_&productId=114309&sortType=&parentId=8-10&filterByKeyWord=iac&categoryNValue=100008&navValue=100278&fromWhere=&itemId=278-10&displayName=Idle+Air+Control+Motor&store=621&skuDisplayName=Idle+Air+Control+Motor+for+Commander+950+and+Digital+Pro-Jection+Systems&brandName=Holley+Performance

[Papabug]

Auto Zone (nope)

well, if it is the motor in the IAC, you may be able to buy a new one. I am not sure if it is available in your area, but check this link:

http://www.autozone.com/autozone/catalog/accessories/accessoriesShelf/detailsFromStoreSelection.jsp?

Don't know if it is what you need or not, but a simple search pulled it up on autozone.com.

Did a search here is what I found or didn't find. :crybaby:
We're sorry, but there are no results in this parts category for your 1991 Ford Festiva-Import 1.3L FI SOHC 4cyl. Please select another vehicle or click on the Parts tab at the top of the page to see the available parts for this vehicle.

Thanks for tryin.

Papabug

[doylerl]

well, if it is the motor in the IAC, you may be able to buy a new one. I am not sure if it is available in your area, but check this link:

http://www.autozone.com/autozone/catalog/accessories/accessoriesShelf/detailsFromStoreSelection.jsp?

Don't know if it is what you need or not, but a simple search pulled it up on autozone.com.