Surging, irregular idle, random no power on accelaration

[freshtiva]

Maybe the vane in your MAF is sticking. I had an idle problem once and took the black top off of the MAF and sure enough the vane was sticking I cleaned and lubed it and the car ran perfect again. It would die at stops. The fuel pump switch is also controlled by the MAF. Just a thought.

[Kofkof_00]

OK, going to get a new TPS. I took it out for a spin, to warm it up, make sure the symptoms were occurring.

Parked in the driveway, idleing (felt like it was idling fast) I watched it go from 900/1000 rpm to 1600rpm without any involvement of my part.

[sasquatch]

maby its the IAC... i got one you can have for free...

[Kofkof_00]

Is the IAC easy to replace?

[sasquatch]

ya... its two hoses and a wire... pm me if you want it...

[Papabug]

Don't think it's the TPS try this first.

F.I. yes? Does the engine idle screw have much effect or little or none?
If so you could warm the car up as usual and after it has reached temp and if your this hose is flexible enough pinch off or plug the hose that goes between the plenum and the Air Control Valve. Hose is on the drivers side goes down behind engine to ACV. If it idles down your ACV may be bad. I had this problem. Trouble is if you want a new one and you can find one they want almost $600 in the US for it.

And hey it's FREE!

[Justin]

Sounds similar to a CTS Sensor going bad. This Sensor Uses Most of your Electrical Volts on Starting/Idling up until Operating Temp. If you have a Ohm Test Gauge hook it up to the terminals across the sensor after uplugging the connector should be cold (not started)(2000 to 3000 ohms) & once the engine reaches operating temperature (180Degrees)(200-400 ohms). Its the best explanation I can Come up w/on Your issues.

[Kofkof_00]

Papabug, I actually read your thread on this problem as part of my research. (Monsoon, are you reading this?) The idle screw has plenty of effect. (you're replacement part is on the list, just going to try it after some of the cheaper ones.)

Justin, having a hard time finding the location of the CTS in my haynes, Is the acronym for "Coolant Temperature Sensor?"

Sasquash, is the one you have known good? I may just order it at Lordco if it isn't too expensive. Go for all new, known good.

The TPS has been ordered. I figure it can't hurt. I'm just going to keep replacing sensors & parts until it gets fixed. :|

[codex]

http://www.fordfestiva.com/forums/showpost.php?p=290455&postcount=9

Please read my post and comment on whether its the same problem you are having.

[Kofkof_00]

Hmmm Your symptoms seem slightly different.

Mine starts on cold, runs fine on cold, once warm, intermittently will have the no power / power symptom.
This general take place when trying to do a smooth acceleration to (low throttle) It has yet to stall as a result.

Yet.

I've listened to the injectors with a long screw driver belt, they are clicking fine. A friend told me the ultimate test for the TPS is to disconnect it while experiencing the symptom. Is that safe? On a running engine?

[Justin]

Is your Car Carberated? Nevermind, I just seen you have EFI. the cts is located in the top center section of the intake manifold under the throttle controls. If you have a Haynes its section 6-9

[Kofkof_00]

OK, I have had the thermostat replaced ($134+$30)

[Kofkof_00]

Still does it. I recorded it. During the recording I pulled the tps, still does it. I have a new tps ($119) to install.

How could I share the .wav file of the engine noise for people to take a guess at? Anyone have ideas? I could setup an ftp server, but shaw won't like that...The idle is all over the place, keep in mind this is with no intervention on my part. Also it sounds like there is a hissing noise. It may be just normal injector noise, I'm going to listen to the white one later tonight, do a comparison.

[freshtiva]

OK, I have had the thermostat replaced ($134+$30)

$164 to replace a thermostat ??

[Kofkof_00]

Yes, that's what people who don't have mechanical skills can expect to pay.