phazed Posted February 20 Author Report Share Posted February 20 Does anybody know what the readings should be for the MAF? Quote Link to comment Share on other sites More sharing options...
½cwt Posted February 20 Report Share Posted February 20 Find any fault codes first.... Quote Link to comment Share on other sites More sharing options...
Sanky Posted February 20 Report Share Posted February 20 4 hours ago, phazed said: Does anybody know what the readings should be for the MAF? should be around 15 kg/h at idle but will vary depending on conditions. If you can read the live value of the MAF, you can remove the oil cap and check that the reading drops to rule out the MAF itself. Quote Link to comment Share on other sites More sharing options...
Sanky Posted February 20 Report Share Posted February 20 (edited) 27 minutes ago, Sanky said: should be around 15 kg/h at idle but will vary depending on conditions. If you can read the live value of the MAF, you can remove the oil cap and check that the reading drops to rule out the MAF itself. Should have added that the reading should be taken with all engine loads off and at operating temp of 90c Edited February 20 by Sanky Quote Link to comment Share on other sites More sharing options...
phazed Posted February 20 Author Report Share Posted February 20 . Excellent. Thank you. I won’t be able to get to the code reader till tomorrow morning. Did a few little things on the car this morning and thought I would run it up. Still started on the button, idled at about 900 RPM. Engine revs climbed immediately when asked for and everything was completely normal. After about three minutes maximum it reverted to a slightly fluctuating idle. When asked to rev, it would start popping back into the manifolds and be reluctant for the revs to rise. Hopefully will get a better idea of what is happening tomorrow when I have access to the code reader? Quote Link to comment Share on other sites More sharing options...
½cwt Posted February 20 Report Share Posted February 20 2 minutes ago, phazed said: . Excellent. Thank you. I won’t be able to get to the code reader till tomorrow morning. Did a few little things on the car this morning and thought I would run it up. Still started on the button, idled at about 900 RPM. Engine revs climbed immediately when asked for and everything was completely normal. After about three minutes maximum it reverted to a slightly fluctuating idle. When asked to rev, it would start popping back into the manifolds and be reluctant for the revs to rise. Hopefully will get a better idea of what is happening tomorrow when I have access to the code reader? Does sound like how mine was behaving when the MAF was duff. Quote Link to comment Share on other sites More sharing options...
Bradders59 Posted February 20 Report Share Posted February 20 I wouldnt rule out a faulty coolant temperature sensor. If it isnt telling the engine ECU that the engine has warmed up, the injectors will keep pumping far too much fuel into the cylinders, which would have a similar effect to a duff MAF giving the wrong info on the amount of air going into the cylinders. Definitely needs diagnostics though. Might be worth looking on the forum map to see if anyone near you has Porsche diagnostics. 1 Quote Link to comment Share on other sites More sharing options...
phazed Posted February 20 Author Report Share Posted February 20 Didn’t know there was a forum map! Good point regarding the coolant sensor. Quote Link to comment Share on other sites More sharing options...
½cwt Posted February 20 Report Share Posted February 20 (edited) 19 minutes ago, phazed said: Didn’t know there was a forum map! Good point regarding the coolant sensor. BoXa Members, Specialists and Track Days - Google My Maps and Durametric owners - Technical Questions & Answers - www.BoXa.net Edited February 20 by ½cwt Quote Link to comment Share on other sites More sharing options...
edc Posted February 20 Report Share Posted February 20 It's sounds like a cold start transition issue. Quote Link to comment Share on other sites More sharing options...
phazed Posted February 20 Author Report Share Posted February 20 34 minutes ago, edc said: It's sounds like a cold start transition issue. Exactly what I was thinking. Although I have no idea where to look for a solution! Quote Link to comment Share on other sites More sharing options...
phazed Posted February 20 Author Report Share Posted February 20 1 hour ago, ½cwt said: BoXa Members, Specialists and Track Days - Google My Maps and Durametric owners - Technical Questions & Answers - www.BoXa.net Thanks for that. I will try my sons code, reader, and see how I get on with it tomorrow morning otherwise, I see there is a guy, Grahamp in Warnham about 15 minutes away from me. Quote Link to comment Share on other sites More sharing options...
edc Posted February 20 Report Share Posted February 20 2 hours ago, phazed said: Exactly what I was thinking. Although I have no idea where to look for a solution! More educated guess work but sounds like a problem with your closed loop running which could be a problem with the lambdas. You can check the lambdas with a tool or even test the AFR at your son's garage with an exhaust probe. Quote Link to comment Share on other sites More sharing options...
phazed Posted February 20 Author Report Share Posted February 20 👍 Quote Link to comment Share on other sites More sharing options...
phazed Posted February 22 Author Report Share Posted February 22 I have just been fiddling around with my son’s code reader. Don’t really know what I’m doing. Give me an engine to rebuild and I am fine but this is a little foreign to me. hopefully I got all these figures in the right order. When warming up. When on idle at about 600 rpm, the MAF is reading in between 19–49 kg/H O2 at idle reads 0.45 V on Banks, one and two O2 At idle reads, 2.05 V on Banks one and two I am assuming that’s the front two O2 sensors and the rear two. Throttle position sensor, 1 is showing 0.76 V Throttle position sensor 2 is showing 4.26 V. When warm. Idle Mass air flow (MAF) 22kg/H Mass air flow. 33.5kg/H Mass air flow sensor 1.45v When warm. Mass air flow (MAF) 38kg/H Mass air flow. 38kg/H Mass air flow sensor 1.75v Can anyone make any sense of this? Quote Link to comment Share on other sites More sharing options...
bally4563 Posted February 22 Report Share Posted February 22 46 minutes ago, phazed said: I have just been fiddling around with my son’s code reader. Don’t really know what I’m doing. Give me an engine to rebuild and I am fine but this is a little foreign to me. hopefully I got all these figures in the right order. When warming up. When on idle at about 600 rpm, the MAF is reading in between 19–49 kg/H O2 at idle reads 0.45 V on Banks, one and two O2 At idle reads, 2.05 V on Banks one and two I am assuming that’s the front two O2 sensors and the rear two. Throttle position sensor, 1 is showing 0.76 V Throttle position sensor 2 is showing 4.26 V. When warm. Idle Mass air flow (MAF) 22kg/H Mass air flow. 33.5kg/H Mass air flow sensor 1.45v When warm. Mass air flow (MAF) 38kg/H Mass air flow. 38kg/H Mass air flow sensor 1.75v Can anyone make any sense of this? What codes is it showing up ? As in P2361 for example Quote Link to comment Share on other sites More sharing options...
phazed Posted February 22 Author Report Share Posted February 22 Didn’t really see any codes. Do all code readers, give these type of codes, are a generic or Porsche specific? I will have to go into it again and see. Quote Link to comment Share on other sites More sharing options...
bally4563 Posted February 22 Report Share Posted February 22 Just now, phazed said: Didn’t really see any codes. Do all code readers, give these type of codes, are a generic or Porsche specific? I will have to go into it again and see. Go in read codes , they are generic on a OBD2 Quote Link to comment Share on other sites More sharing options...
phazed Posted February 22 Author Report Share Posted February 22 👍 Quote Link to comment Share on other sites More sharing options...
bally4563 Posted February 22 Report Share Posted February 22 2 minutes ago, phazed said: 👍 If it’s a decent code reader it should tell you , if not make a note and google it or them Quote Link to comment Share on other sites More sharing options...
phazed Posted February 22 Author Report Share Posted February 22 P0134 sensor ahead of cat. Conv, Bank 1 P0154 sensor ahead of Cat. Conv, Bank 2 Quote Link to comment Share on other sites More sharing options...
bally4563 Posted February 22 Report Share Posted February 22 8 minutes ago, phazed said: P0134 sensor ahead of cat. Conv, Bank 1 P0154 sensor ahead of Cat. Conv, Bank 2 So that’s two Lambda sensors you need or erase the codes and run it up the road again Quote Link to comment Share on other sites More sharing options...
iborguk Posted February 22 Report Share Posted February 22 P0134 Oxygen sensor upstream NOTE The fault "Over limit value" is detected if the oxygen sensor voltage is > 1.5 V for an uninterrupted period of more than 5 s. Diagnostic conditions DME control module power supply 10.5 V … 16 V Oxygen sensor heater switched on for > 70 s Oxygen sensing active Exhaust temperature 600 °C (1,112 °F)... 750 °C (1,382 °F) min. 3 s overrun No secondary air injection or diagnosis of secondary air system active No tank ventilation or diagnosis of tank ventilation system active No other oxygen-sensor faults stored Possible fault causes Fault in oxygen sensor heater A If this exists, is to be taken care of first Loose contact or corrosion in the connector Short circuit to B+/ground/between wires or open circuit in the wiring Heater injection Oxygen sensor faulty DME control module faulty Quote Link to comment Share on other sites More sharing options...
iborguk Posted February 22 Report Share Posted February 22 (edited) P0154 Oxygen sensor upstream NOTE The fault "Over limit value" is detected if the oxygen sensor voltage is > 1.5 V for an uninterrupted period of more than 5 s. Diagnostic conditions DME control module power supply 10.5 V … 16 V Oxygen sensor heater switched on for > 70 s Oxygen sensing active Exhaust temperature 600 °C (1,112 °F)... 750 °C (1,382 °F) min. 3 s overrun No secondary air injection or diagnosis of secondary air system active No tank ventilation or diagnosis of tank ventilation system active No other oxygen-sensor faults stored Possible fault causes Fault in oxygen sensor heater A If this exists, is to be taken care of first Loose contact or corrosion in the connector Short circuit to B+/ground/between wires or open circuit in the wiring Heater injection Oxygen sensor faulty DME control module faulty Edited February 22 by iborguk Quote Link to comment Share on other sites More sharing options...
½cwt Posted February 22 Report Share Posted February 22 28 minutes ago, bally4563 said: So that’s two Lambda sensors you need or erase the codes and run it up the road again Slightly strange that both pre cat lambdas would go at the same time, however for 2003 onwards part number 986 606 226 00 or Bosch 0 258 986 602 about £55 each from Autodoc or avaiable for a little more from your local Bosch auto electrical stockist or a lot more for the Porsche boxed identical Bosch part from your local OPC.... 1 Quote Link to comment Share on other sites More sharing options...
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