Unregisterable, unsellable, all because of an elusive IAT CEL.
- Thread starter AverageFiestaEnjoyer
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OP
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#24
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#24
hmm ok. I will order the CRC spray and try it on the connector from jpg0840. Also, to confirm, what is that connector? Is that the MAF sensor?
Also I think I can empty the catch can since I watched my cousin do it once. He sprayed it with brake cleaner or something when he did clean it. Should I do that too?
thank you typhoon. I appreciate your patience and help!
Also I think I can empty the catch can since I watched my cousin do it once. He sprayed it with brake cleaner or something when he did clean it. Should I do that too?
thank you typhoon. I appreciate your patience and help!
Yes it's simple. Only 2 allen bolts to remove. I wouldn't fire the parts canon in before establishing a good diagnostic though.
I'd try to find which 2 pins are connected to the IAT and what resistance you should get when at the pins at a given temperature with it unplugged from the harness. (Alldata for a 1 month subscription of 20$ should give you this information. Sadly it's not something that is given by the readily available ford service manual). If the results are within specs with a multimeter and the pins look good, not bent or corroded, you can rule out the MAF sensor as the culprit.
Then I'd do the same test but with the MAF plugged in the wire harness, and with the ECU unplugged. So taking your measurement at the wire side of the ECU plug, you can check that you have the same resistance that you had previously at the MAF directly. If it's the same, then I'd also rule out the wiring harness.
I'd try to find which 2 pins are connected to the IAT and what resistance you should get when at the pins at a given temperature with it unplugged from the harness. (Alldata for a 1 month subscription of 20$ should give you this information. Sadly it's not something that is given by the readily available ford service manual). If the results are within specs with a multimeter and the pins look good, not bent or corroded, you can rule out the MAF sensor as the culprit.
Then I'd do the same test but with the MAF plugged in the wire harness, and with the ECU unplugged. So taking your measurement at the wire side of the ECU plug, you can check that you have the same resistance that you had previously at the MAF directly. If it's the same, then I'd also rule out the wiring harness.
OP
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#31
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even something like this intimidates me. Worried I’ll mess it up and break my car if I mismatch the wires or forget how to put things back together. Might just bring it to a mechanic to test this, but I’ll try looking at it. By the way I like the Anubis in your profile picture. Super cool! Thank you Alkoran
Yes not unusual for techs not to work on altered vehicles as it's not exactly unusual that backyard engineering creates issues; both immediate and/or long-term. I let a prior engine run cold because of the reliability and performance benefit and it took years before the consequences of that decision became obvious. Something as simple as misrouting, not properly securing or using an "add-a-circuit" product can have unintended or serious consequences at some unknown point down the road.
Take the other bolt from the MAP to the hardware store and match it up; depth/thread/diameter. Store clerk will help. The smaller stores like ACE are better for this.
Does the code change when the IAT sensor is unplugged? What does it change to?
What is that second code? It may be related. Don't ignore it. Do they share a harness? Any abrasion, heat or other damage? Does the code change when unplugging the sensor?
View: https://youtu.be/u-2UDKpdonk
Oil on the IAT sensor doesn't sound normal? The sensor's housing and tube will be just as contaminated and that contamination may quickly spread.
Manufacturers of N/A engines typically use either MAP or MAF but not both. Does the FiST employ MAF in addition to the MAP or is that just IAT? The fact that it's four wire does suggest more than IAT. Prior experiences suggest MAF will be completely useless if contaminated in the slightest. Looking at how your altered intake is routed, may provide clues as to how this is occurring and what needs to be done to truly address this. Are the turbo seals good? PCV in my prior vehicle was routed well downstream of the MAF and IAT so it was impossible for it to contaminate the delicate MAF or skew IAT readings.
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Take the other bolt from the MAP to the hardware store and match it up; depth/thread/diameter. Store clerk will help. The smaller stores like ACE are better for this.
Does the code change when the IAT sensor is unplugged? What does it change to?
What is that second code? It may be related. Don't ignore it. Do they share a harness? Any abrasion, heat or other damage? Does the code change when unplugging the sensor?
Oil on the IAT sensor doesn't sound normal? The sensor's housing and tube will be just as contaminated and that contamination may quickly spread.
Manufacturers of N/A engines typically use either MAP or MAF but not both. Does the FiST employ MAF in addition to the MAP or is that just IAT? The fact that it's four wire does suggest more than IAT. Prior experiences suggest MAF will be completely useless if contaminated in the slightest. Looking at how your altered intake is routed, may provide clues as to how this is occurring and what needs to be done to truly address this. Are the turbo seals good? PCV in my prior vehicle was routed well downstream of the MAF and IAT so it was impossible for it to contaminate the delicate MAF or skew IAT readings.
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Whenever there is a seal guarding the contacts, this is exactly right. Lube the seals instead. They will protect the connectors from exposure to air. No air exposure and they won't oxidize. If the seals are bad, address the seals. If the contacts or conductive metals are exposed to open air, then coating them directly will benefit. Had to do this with a dome light bulb and door jamb switches in a prior vehicle. Both were open exposed to air; no seals protecting them.
This Individual simply needs to take their car to a shop that will actually be willing to fix the vehicle plan and simple. This individual is not a mechanic, and this is not a beginners level problem. Find a shop ask around if necessary. I would help you out if I lived in your area.
Next this has been said many times on this site over the years. In the USA market the cars are tuned off the MAP. Over the pond they are tuned off the MAF. In the USA market it works as a IAT.
Last Aftermarket air filters they are not over oiled do not hurt the MAF at all. Only when people over oil them. This has been discussed for over 20 years in the car community, and I can't believe it is still being discussed. I have never had a MAF failure in any vehicle in my life with a Aftermarket oiled air filter. May sound rude do not care, I am not here to be your friend, but to be blunt and to the point. The focus needs to be on both codes as the person above pointed out there could be a connection for sure. Ones again find a real shop. Good luck to you.
Next this has been said many times on this site over the years. In the USA market the cars are tuned off the MAP. Over the pond they are tuned off the MAF. In the USA market it works as a IAT.
Last Aftermarket air filters they are not over oiled do not hurt the MAF at all. Only when people over oil them. This has been discussed for over 20 years in the car community, and I can't believe it is still being discussed. I have never had a MAF failure in any vehicle in my life with a Aftermarket oiled air filter. May sound rude do not care, I am not here to be your friend, but to be blunt and to the point. The focus needs to be on both codes as the person above pointed out there could be a connection for sure. Ones again find a real shop. Good luck to you.
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Over oiling generally doesn't result with a slathering of oil down the line, nor with MAF failure. It does however contaminate the MAF, which means you have to keep cleaning it from time to time. (too much for the heated wire to burn off) Had to keep cleaning an MAF with a dry Purolator brand "performance" air filter. It was too thin... went back to OEM standard type air filter. (there are many "performance" products that are not intended for use on the street... Purolator didn't put that on their package)
IAT = Idle Air Temp
MAF = Mass Air Flow
They perform different functions.
IAT = Idle Air Temp
MAF = Mass Air Flow
They perform different functions.
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