Car Stuck In Safety Mode. Please Help

[simpledan]

Hi there,

need the car urgently for the kids but has developed a fault.

here goes

car is a 2000 ghia x auto 2.0l mondeo

Basically it wont shift gear, goes up to around 30miles or so and then wont shift gear any higher. everything else seems to be fine. i believe it is in safety mode also called limp mode

it does eat petrol like crazy but that has always been the case and has always driven fine.

ran a diagnostics and the code is

P0113 IAT Circuit High Input

will fixing the cause of the p0113 code fix the limp mode issue or could there possibly be another mechanical issue?

any help on this matter? what should i do? thanks

[jeebowhite]

The error:

The powertrain control module (PCM) monitors the temperature of the air entering the engine. The PCM supplies a 5 volt reference voltage to the Intake Air Temperature (IAT) sensor. The IAT is a thermistor that varies resistance based on temperature. As the temperature increases, resistance decreases. Low temperature results in a high signal voltage. When the PCM sees a signal voltage higher than 5 volts, it sets this P0113 check engine light code.

The Cause:

•Internally failed IAT sensor

•Faulty connection at IAT sensor

•Open in IAT ground circuit or signal circuit

•Short to voltage in IAT signal circuit or reference circuit

•IAT harness and/or wiring routed too close to high-voltage wiring (e.g. alternator, spark plug cables, etc.)

•Faulty PCM (less likely but not impossible)

Solutions:

First, if you have access to a scan tool, is there an IAT reading? If the IAT reading is logical then the problem is likely intermittent. If the reading is less than -30 degrees, unplug the connector. Install a jumper wire between the harness connector signal and ground circuits. The IAT temperature reading on the scan tool should be maxed out at the high end. For example it should be 280 degrees Farenheit or higher. If it is, the wiring is okay, and it may have been the connection. If it isn't install the jumper wire between the IAT signal circuit and the chassis ground.

If now the IAT reading on the scan tool is maxed out then check for an open in the IAT ground circuit. If you get no reading at all on the scan tool, it's likely that the sensor signal is open or the 5 volt reference is missing. Check using a DVOM (digital volt ohm meter) for a 5 volt reference. If it's there, then unplug the connector at the PCM and check for continuity on the IAT signal circuit between the PCM connector and the IAT connector.

Other IAT sensor and circuit related DTCs: P0095, P0096, P0097, P0098, P0099, P0109, P0110, P0111, P0112, P0114

Because of the fault being the PCM thats why you are in limp home mode! if you resolve the issue yes, you should get out of limp home mode. I presume, although you advise you have problems shifting, you can still shift between all 6/7 gears?

[simpledan]

Hi, many thanks for the reply. Appreciate that.

No i cant shift between the gears, it just seems to be stuck in one gear at the moment. Goes upto around 20/30 miles fine and then the rpms go into the red and speed does not increase. Reverse gear works fine, and gear D is fine up until 20/30 miles. (it is a 4 gear automatic )

However, few days before the car went into limp mode, it seemed to judder/shake all over (abit like an earthquake, not able to pin point but seemed to be coming from the middle of the car) this judder was just before slowing down from a higher speed. (say from coming down from 30/40 to red lights) once at the red lights it seemed to judder and shake for no reason even at 0 miles.

few days after this shaking problem the car went into limp mode. Not sure if this shake was down to the IAT sensor error. There are no warning lights on at the dashboard.

Sorry for such a basic question but do you think if i get the Mass Airflow Sensor replaced the IAT problem will be fixed? (having checked all the other connection/possibilities etc which you talked about before)

Thanks

[jeebowhite]

Hi, many thanks for the reply. Appreciate that.

No i cant shift between the gears, it just seems to be stuck in one gear at the moment. Goes upto around 20/30 miles fine and then the rpms go into the red and speed does not increase. Reverse gear works fine, and gear D is fine up until 20/30 miles. (it is a 4 gear automatic )

However, few days before the car went into limp mode, it seemed to judder/shake all over (abit like an earthquake, not able to pin point but seemed to be coming from the middle of the car) this judder was just before slowing down from a higher speed. (say from coming down from 30/40 to red lights) once at the red lights it seemed to judder and shake for no reason even at 0 miles.

few days after this shaking problem the car went into limp mode. Not sure if this shake was down to the IAT sensor error. There are no warning lights on at the dashboard.

Sorry for such a basic question but do you think if i get the Mass Airflow Sensor replaced the IAT problem will be fixed? (having checked all the other connection/possibilities etc which you talked about before)

Thanks

Not what you want to hear but it sounds like your gearbox is shot, and the IAT is probably the least of your worries. The likelyhood is the gear assembly is worn, or damaged to a point it cant shift out of first gear in auto mode. What if you shunt it to 1 - 2? having never driven an Auto I dont know what gears you can go from and to, so dont know if you can jump from 2 - D or not.

[simpledan]

Not what you want to hear but it sounds like your gearbox is shot, and the IAT is probably the least of your worries. The likelyhood is the gear assembly is worn, or damaged to a point it cant shift out of first gear in auto mode. What if you shunt it to 1 - 2? having never driven an Auto I dont know what gears you can go from and to, so dont know if you can jump from 2 - D or not.

Again thanks for the reply. Got it checked out today, the mechanic done a diagnostics and reset the codes (something like that) then he told me to drive it and surprisingly it shifted gear fine. he had no idea himself why it was stuck in limp mode. so i am very pleased but also surprised a car would be in safety mode for no reason?

however the problem which first started the limp mode, which was the judder/shake of the car when at the traffic light (always at 0 speed, or just coming to a stopping speed) is still happening.

he said drive it around for a few days and let the error codes come back up and he will run the diagnostics again.

i want to ask, any ideas what this judder/shake problem is due to?? the mechanic could not tell himself.

[btmaldon]

i want to ask, any ideas what this judder/shake problem is due to?? the mechanic could not tell himself.

I assume the judder and shake is occuring while it is still in gear. Does it do it if you drop it into neutral?

If this is only happening whilst in gear, it could just be the gearbox mount or even an engine mount that needs replacing.

The only other thing you can check is the gearbox oil level is correct.

[simpledan]

hi, thanks for the reply. the gearbox oil is fine. yes the mini earthquakes happen whilst in Drive gear and fully stopped ( say at traffic lights)

next time the judder/shakes happen whilst stopped i will stick it in neutral and report back saying if that stopped the shaking or not.

mechanics seem to be lost. do you guys think its anything which can be overly dangerous? even though the problem happens only at a stop, the car wont suddenly stop working on the dual carriage way will it? cheers

[jeebowhite]

hi, thanks for the reply. the gearbox oil is fine. yes the mini earthquakes happen whilst in Drive gear and fully stopped ( say at traffic lights)

next time the judder/shakes happen whilst stopped i will stick it in neutral and report back saying if that stopped the shaking or not.

mechanics seem to be lost. do you guys think its anything which can be overly dangerous? even though the problem happens only at a stop, the car wont suddenly stop working on the dual carriage way will it? cheers

Shouldnt do, by he sounds of it, its possibly struggling to change down a gear as it pulls to a halt. Should then flick down the gears and into neatral at a stand still...

unless you get that feeling whilst driving generally which it doesnt seem you do, I cant see any reason why it would conk out at speed.

[simpledan]

evening all. and heres my diary of the day.

Car drove fine for about 50-60 miles today and at night time at the traffic lights when i was just going home it started to shake. been fine all day drove fine even at high speed. a guy i mentioned the problem to said the petrol filter might need to be changed or the spark plugs. (have had both these changed about 3500 mile ago) could these be the cause. i really dont think they would be though...

[jeebowhite]

evening all. and heres my diary of the day.

Car drove fine for about 50-60 miles today and at night time at the traffic lights when i was just going home it started to shake. been fine all day drove fine even at high speed. a guy i mentioned the problem to said the petrol filter might need to be changed or the spark plugs. (have had both these changed about 3500 mile ago) could these be the cause. i really dont think they would be though...

I dont quite understand why they would be the issue especially if recently replaced. Plus, you would have problems at high speed, also, (in fact more likely to have more problems at high speed!) the problem occurs only when slowing down to a stop.

Have you thrown a mechanic into the driver seat yet? you should drive him in the passenger seat to show him, then get them to replicate it.

you can change all your filters to try and resolve it, but other than the spark plugs, could be coils and HT leads that need replacing, I really dont know if this will help but I suspect not. Having said that replacing them all would probably be cheaper than 1 hours Ford labour...

[btmaldon]

evening all. and heres my diary of the day.

Car drove fine for about 50-60 miles today and at night time at the traffic lights when i was just going home it started to shake. been fine all day drove fine even at high speed. a guy i mentioned the problem to said the petrol filter might need to be changed or the spark plugs. (have had both these changed about 3500 mile ago) could these be the cause. i really dont think they would be though...

Did you try putting it into neutral?

Thing is, whilst it is in drive, it is only the brakes that are holding the car from driving itself forward. So you will have a load on the engine and gearbox whilst you a stationery, unless you take it out of gear. Its not supposed to be left in gear for any period of time when stationery anyway.

[simpledan]

hi there, quick note on the problem.

the car is driving fine, however the acceleration is pretty weak, especially when going up from 0 to about 20. seems to need alot more power to keep up in the slow lane on the motorway. so overall not a normal drive like it used to be.

judder, which is the main problem. happens in all gears, including parked gear (not noticed it happening in reverse gear so far)

the main time it shakes/judders is at 0 miles. im dreading any traffic lights as the car seems to judder when at a stop. the judder sometimes happen even just after i have started the car and it is still in parked gear. so it does not seem to happen when coming to a stop BUT when at an actual stop. no mechanic can pin point it. not sure what else to say or do to fix the judder problem. very lost

[digidash]

i presume scanner used to get iat code was not ford??? i would suggest getting it plugged into ids which can pull transmition codes. try phoning local electricians as some of us have it and i charge £25 for diagnostics session which will read every module on a car then go into live data to monitor systems with faults. when you checked auto oil was car warm and ticking over? where in uk are you? regards steve

[simpledan]

i presume scanner used to get iat code was not ford??? i would suggest getting it plugged into ids which can pull transmition codes. try phoning local electricians as some of us have it and i charge £25 for diagnostics session which will read every module on a car then go into live data to monitor systems with faults. when you checked auto oil was car warm and ticking over? where in uk are you? regards steve

hi there, thought i would get back to this thread in case sum one ever has a similar problem and is googling for a solution.

the car drives fine. been driving for few weeks fine now, but am living with the juddering problem at the traffic lights still.

in response to your post steve..

firstly thanks for the reply and im not actually sure whichdiagnostics tool was used initially, so cant really comment on that question. i think it was them universal ones that plug into any car make? dont think it was an actual specific ford one. im down london myself. last time i checked the automatic oil the car was cold...

[p38fln]

There was a code for a bad IAT? I had the IAT sensor destroyed in a 1987 Cadillac Sedan DeVille when the engine backfired because part of the rocker arm assembly broke. Replaced the broken rocker arm assembly, and then the engine ran fine when cold, but began missing and running very rough as it warmed up. Code for a bad IAT came up on the computer, and after I replaced it, the car ran fine.

GM had their computers programmed to use the engine coolant sensor as a backup for the intake air temperature sensor... Rather stupid, since as the engine warmed up, it got further and further from the actual air temperature.