Pumapeople: Automatic Choke/cold Start Issues - Pumapeople

Hi i have a ford 1.7 16 v 2001 panther puma when i start this from cold the choke does not come on does anybody no the location of the choke and where to find this please .if you have pictures of what it looks like it would be most greatfull and how to test this also.
i have been told that there is no choke as such ,but when started from cold it will not tick over unless your foot is resting on the gas,then it idles at very low revs until
it warms up . i have plugged this up and and i get a fault code P1504 which is IAC malfunction we have changed this for tWo seperate ford new ones and reset the ecu
and even check the wiring back to the Ecu but after a few miles driving it comes back with the same fault,does any body no how to resovle my issues reference
cold start/and IAC malfunction...???

This post has been edited by sahara1: 30 December 2011 - 11:58 AM

Hi, the puma dosn't have a choke, the choke was mostly abandond in the late 80's
it does however have an automatic "cold start" function, it uses the sensors in the engien to determine how mutch fuel is needed to start from cold, and is regulated constantly as the temprature rices.

you may have a faulty temperature sensor, or a faulty idle controler, or a foulty air mass sensor. or it could be something compleetly different

I ad a simular issue just yesterday, mine keept stoping at the lights when cold, I clened the idle control valve, but that did nothing, then I clened the air mass meter plug and it was back to normal again.

edit: missed the part whit the fault code. not shure what that code meens right at this moment. I'l get back to you when I do

This post has been edited by CartMan: 30 December 2011 - 02:09 PM

a quick google search provided this

Code p1504 sets when the PCM detects an electrical load failure on the IAC output circuit.



What does this mean? The idle air control valve is powered by the VREF circuit. This circuit also feed the fuel injectors , emisson control solenoids, etc. It finds its ground through a PWM (Pulse Width Modulated) control circuit in the PCM. The PCM increases or decreases the PWM signal as necessary to open the iac valve to maintain idle. The PWM signal can be monitored with a scantool and is typically found somewhere near 30-35%.



Is the car idling low or high?



The electrical resistance of the valve should be 6 to 13 ohms. The resistance from either pin to the case must be greater than 10,000 ohms (10kOhms) I have seem some replacement valves that have incorporated a diode in them. In some cases, the replacment part has the diode reversed. Are you using a genuine Ford part ?



Make sure that the RPM drops when the IAC valve is disconnected. Most cars will go to a very low idle speed and almost stall when the iac valve is disconnected. If the vehicle continues to idle normally or higher than normal, there may be a vacuum leak . This will usually set codes other than the one you have reported.



Important note: By the information you have provided in your post, a full test has yet to be completed. Ford products have a "quick test" procedure that requires an enhanced scantool. A generic OBD2 scanner will only report history codes. The enhanced test will include History codes, Key On Engine Off codes and Key On Engine Running codes. I would strongly suggest that you get these tests done before investing any more money in parts. Other codes may come up during those tests that will point you in a different direction.



There is an engine data item that reports the current commanded position for the IAC valve. With the engine at idle, the IAC data pid should show somewhere between 20 and 40 % . Try wiggling the harness and watch this value for change. If this produces a change, you have identified and need to correct a harness problem.



Addtional note: make sure battery cables are clean and secure. Poor ground cable connections can cause all manner of problems with these cars

Hi thankyou for your reply

before posting this we have replaced the above items listed.

we have cleaned MAF UNIT and even tried a second hand working one which still did not change anythink.

AIR VACUME PIPES HAVE BEEN CHECKED AND THERE IS NO SIGNS OF PIN HOLES/OR EVEN NO SIGNS OF PERISHED

DO YOU THINK THE COLD START ISSUE WOULD STOP THE IAC VALVE FROM WORKING AS WE HAVE TESTED THIS WHEN THE IGNITION IS ON IT READS 4VOLTS
WHEN ENGINE IS RUNNING IT READS 14.4 VOLTS.

YOU MENTIONED faulty temperature sensor , IS THIS THE AIR TEMPERATURE SENSOR OR THE THERMASTATE TEMPERATURE SENSOR.

YOU ALSO MENTIONED SENSOR WHAT SENSORS HOW MUCH FUEL IT NEEDS TO PUT IN WHEN ITS COLD WHERE CAN I FIND THIS AND HOW COULD THIS BE TESTED.

Is the car idling low or high? CAR IDLES VERY LOW WHEN COLD / BUT WHEN IT HAS WARMED UP IT IDLES NORMAL

BUT YOUR FOOT NEEDS TO BE ON THE GAS WHEN COLD TILL IT GETS WARM

P1504 READS ON FORD CODE AS IAC MALFUNCTION

WE HAVE BEEN PLAYING ABOUT WITH THIS FOR OVER A MONTH AND WE ARE LOOSING THE WILL TO LIVE WITH THIS IF YOU COULD RESOVLE OUR ISSUES
WE WOULD BE MOST GREATFULL

I'm thinking of the coolant temp sensor.
as to "YOU ALSO MENTIONED SENSOR WHAT SENSORS HOW MUCH FUEL IT NEEDS TO PUT IN WHEN ITS COLD " this is a calculation made from the input of all the engiens sensorrs at the moment of start and continous as it idels/runs

Is there anything you remember happening before this problem ocured?? or is it a case of ok when parked, problem the next day??

problems like this are a pain I know, it's realy frustrating.

i'm thinking realy hard, ut i'm koming up blank at the moment

CartMan, on 02 January 2012 - 03:59 PM, said:

We had 2 ford puma's the older one started up with the cold start working fine then we got rid if this due to serious mot failer. Then we bought 2001 year one and when we picked this up the engine was okay because
it was warm the following cold morning we relised that it would not idle without your foot on the gas until it warms up so we started to investagate this and we have checked and changed numerous of the above
part but still we have had no joy. And we can't find the problem what is causing these faults.. ITS FRUSTRATED US FOR QUITE SOME TIME NOW.

IM NOT SURE IT COULD BE THE COOLANT TEMP AS THIS WORKS OKAY ON THE DASH.

Hmmm. bummer.

How is the service history?? has the fuel filter been changed?? could the oil be old an sirupy?? not many things change from cold to hot ;/

This post has been edited by CartMan: 03 January 2012 - 08:34 PM

CartMan, on 03 January 2012 - 09:52 AM, said:

Oil and filter is okay changed recently.

and the fuel filter??

sahara1, on 03 January 2012 - 11:21 AM, said:

Hi i dont think the fuel filter will cause the cold start and the IAC vavle issue to be thruthfull

the eingien needs less fuel when hot than cold you know, a realy cloged fuel filter may cause it to stopp, and as there is no truble codes for the filter, it can register it as a fault in the iac, I agrre that it might be unlikely, but if all else fails, the unlikely becomes the likely cause have also seen faulty fuel pumps do this, but not on a puma.

i think it is the throttle position sensor personally. They are crap. Problems like this are such a pain. I resorted to going to a scrap yard and robbing every sensor of a puma. If i ever get a fault i try 3 other sensor on each one. Usually it finds the problem. Where abouts are you because i have parts on the shelf.

CartMan, on 04 January 2012 - 08:03 AM, said:

i will try that because i have not changed that yet and we do not know when it was last changed

volcomstone411, on 04 January 2012 - 09:54 AM, said:

Hi we are in lancashire, I will try what you said with the TPS and the other sensors.

CartMan, on 04 January 2012 - 08:03 AM, said:

There was something i noticed when i was keeping the tick over on the car with my hand on the throttle lever under the bonnet i heard the water thermostate spring open in its housing .
Then i let go of the throttle lever because the engine was warm and it ticks over fine ,this is not the first time i have heard this... What are you views on this
because that is part of the warming process

This post has been edited by sahara1: 04 January 2012 - 11:29 PM