Indi
Member
I have been hunting this engine light on and off for months now and have come back with nothing.
A year or two ago I had a load of fault codes, (including the one mentioned as far as I remember) these were mainly electrical and mostly fixed by a new alternator and eventually a new battery too. The car was sat unused for a few terms while I was at university, and a missing bonnet drain cup meant water was being funneled onto the alternator. This fixed most of the issues, except a code for the EGR valve which I replaced solving the issue.
There was then a clear patch with only occasional intermittent codes (I cant really remember, but possibly EGR valve and Intake manifold pressure sensor) and stretches of no engine light in between.
Then 6 months ago maybe started getting codes for the manifold pressure sensor and load calculation cross check more and more frequently.
17550 - Load Calculation Cross Check
P1142 - 35-10 - Lower Limit Exceeded - Intermittent
17961 - Barometric / Manifold Pressure Signals
P1553 - 35-10 - Implausible Correlation - Intermittent
The obvious suspect was the manifold combined pressure/temp sensor, as this is used instead of a MAF in the 1.4 MPI so would explain both codes. However replacing it didn't fix the Load Calculation Cross Check code, though it did seem to get rid of the Manifold Pressure code.
On the Ross Tech Website it lists the following:
As I said earlier, there is no MAF, but G70 refers to the Manifold pressure sensor on the 1.4 MPI, which I had already replaced.
I had poked around with the intake system a year or two ago when I did the alternator, and noticed a mouse had chewed the rubber off the flap that switches between the hot and cold intakes, It was not available new or aftermarket anywhere I could find, and the second hand one I got was in worse shape than the original, so just put it back together as is. This is all upstream of the G70 sensor so as far as I can tell should not be causing the errors I have.
I decided to double check the air intake system and change the air filter, and found the mouse damage was more extensive than I had realised:
Changing the filter didn't help and the light came back after a day or two.
Next I decided the throttle body and EGR adaption, as I did not do this when changing the EGR valve as I didn't have VCDS at the time.
Without resetting the codes, the light disappeared for a almost a week, (using the car twice a day for about 12 miles) the longest it had stayed off in a long time, however after the brief interlude returned to lighting up every trip. The EGR code has not showed up again since.
I checked the four other sensors listed, but only one seems present on the 1.4 (G79 iirc) and it seemed to go through a range of values as I pressed the pedal, though I didn't probe any further than that.
Over the weekend I drove about 750 miles over 4 trips, and at the end of trip 3 the ABS warning beeped at me and all the associated lights came on on the dash, But the brakes were fine, instead just telling me to check the engine DTCs:
01314 - Engine Control Module
013 - Check DTC Memory - Intermittent
The engine module showed
17550 - Load Calculation Cross Check
P1142 - 35-10 - Lower Limit Exceeded - Intermittent
17961 - Barometric / Manifold Pressure Signals
P1553 - 35-10 - Implausible Correlation - Intermittent
Which was the first time the manifold pressure code had showed up in the several months since I'd changed the sensor.
I did not reset the codes, but the brake lights went away when I turned off the car, though it did come on again once.
Further info;
The car is a 1.4 Petrol BBY, 115k miles, still drives fine, I don't notice any difference in power or economy, returned 55mpg @ 55mph over the weekend. I run it on E5.
A month or two ago I tried logging some trips with VCDS to try to catch the error and associated sensor graphs as it happened, but over the two trips the light conveniently did not show up.
I had been driving the car for over a year with the filter in that state, and miraculously seems to have suffered no consequences (unless this is somehow related) I presume it was all soft mouse nest materials so just got burned off without causing too much damage.
Thanks for reading, I have reached a bit of a wall so thought I'd see if anyone else had any ideas.
Cheers,
Indi
A year or two ago I had a load of fault codes, (including the one mentioned as far as I remember) these were mainly electrical and mostly fixed by a new alternator and eventually a new battery too. The car was sat unused for a few terms while I was at university, and a missing bonnet drain cup meant water was being funneled onto the alternator. This fixed most of the issues, except a code for the EGR valve which I replaced solving the issue.
There was then a clear patch with only occasional intermittent codes (I cant really remember, but possibly EGR valve and Intake manifold pressure sensor) and stretches of no engine light in between.
Then 6 months ago maybe started getting codes for the manifold pressure sensor and load calculation cross check more and more frequently.
17550 - Load Calculation Cross Check
P1142 - 35-10 - Lower Limit Exceeded - Intermittent
17961 - Barometric / Manifold Pressure Signals
P1553 - 35-10 - Implausible Correlation - Intermittent
The obvious suspect was the manifold combined pressure/temp sensor, as this is used instead of a MAF in the 1.4 MPI so would explain both codes. However replacing it didn't fix the Load Calculation Cross Check code, though it did seem to get rid of the Manifold Pressure code.
On the Ross Tech Website it lists the following:
17550/P1142/004418 - Load Calculation Cross Check: Lower Limit Exceeded
Possible Causes
- Mass Air Flow Sensors (G70) faulty
- Intake Air System faulty/leaking (false Air)
- Throttle Pedal faulty
- Throttle Body dirty/faulty
Possible Solutions
- Check Mass Air Flow Sensors (G70)
- Check Intake Air System
- Check Throttle Pedal
- Check Throttle Pedal Position Sensor (G79)
- Check Throttle Pedal Position Sensor 2 (G185)
- Check Throttle Body
- Check Angle Sensor 1 for Throttle Actuator (G187)
- Check Angle Sensor 2 for Throttle Actuator (G188)
- Check Engine Control Unit
As I said earlier, there is no MAF, but G70 refers to the Manifold pressure sensor on the 1.4 MPI, which I had already replaced.
I had poked around with the intake system a year or two ago when I did the alternator, and noticed a mouse had chewed the rubber off the flap that switches between the hot and cold intakes, It was not available new or aftermarket anywhere I could find, and the second hand one I got was in worse shape than the original, so just put it back together as is. This is all upstream of the G70 sensor so as far as I can tell should not be causing the errors I have.
I decided to double check the air intake system and change the air filter, and found the mouse damage was more extensive than I had realised:
Changing the filter didn't help and the light came back after a day or two.
Next I decided the throttle body and EGR adaption, as I did not do this when changing the EGR valve as I didn't have VCDS at the time.
Without resetting the codes, the light disappeared for a almost a week, (using the car twice a day for about 12 miles) the longest it had stayed off in a long time, however after the brief interlude returned to lighting up every trip. The EGR code has not showed up again since.
I checked the four other sensors listed, but only one seems present on the 1.4 (G79 iirc) and it seemed to go through a range of values as I pressed the pedal, though I didn't probe any further than that.
Over the weekend I drove about 750 miles over 4 trips, and at the end of trip 3 the ABS warning beeped at me and all the associated lights came on on the dash, But the brakes were fine, instead just telling me to check the engine DTCs:
01314 - Engine Control Module
013 - Check DTC Memory - Intermittent
The engine module showed
17550 - Load Calculation Cross Check
P1142 - 35-10 - Lower Limit Exceeded - Intermittent
17961 - Barometric / Manifold Pressure Signals
P1553 - 35-10 - Implausible Correlation - Intermittent
Which was the first time the manifold pressure code had showed up in the several months since I'd changed the sensor.
I did not reset the codes, but the brake lights went away when I turned off the car, though it did come on again once.
Further info;
The car is a 1.4 Petrol BBY, 115k miles, still drives fine, I don't notice any difference in power or economy, returned 55mpg @ 55mph over the weekend. I run it on E5.
A month or two ago I tried logging some trips with VCDS to try to catch the error and associated sensor graphs as it happened, but over the two trips the light conveniently did not show up.
I had been driving the car for over a year with the filter in that state, and miraculously seems to have suffered no consequences (unless this is somehow related) I presume it was all soft mouse nest materials so just got burned off without causing too much damage.
Thanks for reading, I have reached a bit of a wall so thought I'd see if anyone else had any ideas.
Cheers,
Indi