Gary Lewis Posted April 1, 2018 Share Posted April 1, 2018 Well that code went away, but messing with that whole harness is revealing some issues for sure. Now, back to square one with no start hot or start / stall. Not even terribly hot, starting it cold which it does like a dream, idles perfectly for 5-10 mins, shut engine off, crank no start. Spark is good at distributor so I can't imagine it would be the ICM (distributor-mounted). Fuel is coming through based only on the smell and the engine sounds flooded after multiple attempts. Stored codes are 31 and 63, both related to the earlier mentioned splice of orange/white wires and not to a starting issue. Never get a chance for KOER testing unless I do it cold which I understand is not recommended. I'll let Bill work with you on that. Bill - I have the documents here: Fuel Systems/Diagnostics. Link to comment Share on other sites More sharing options...
mp470 Posted April 2, 2018 Author Share Posted April 2, 2018 I'll let Bill work with you on that. Bill - I have the documents here: Fuel Systems/Diagnostics. I know it's a lot to process, sorry to be a nuisance. Anyways, I got back out there just to start from scratch. Didn't even turn the key this time, purely for sensor resistance checks and to write everything down this time. ECT was 124k ohms and ACT was 126. It's about -5C outside. Too far out of range, or perhaps they need to be warmed up before testing? Link to comment Share on other sites More sharing options...
Gary Lewis Posted April 2, 2018 Share Posted April 2, 2018 I know it's a lot to process, sorry to be a nuisance. Anyways, I got back out there just to start from scratch. Didn't even turn the key this time, purely for sensor resistance checks and to write everything down this time. ECT was 124k ohms and ACT was 126. It's about -5C outside. Too far out of range, or perhaps they need to be warmed up before testing? You still need Bill, but at -5C it looks like the ECT should have been about 70k ohms instead of 124k. That's way out of range, but I don't think it would cause a huge problem since all that tells the computer is that it is REALLY cold out - like about -50 C. But the engine should still start and run. The real question is what the ECT resistance is when the coolant is up around 80 degrees C or 180 F. But I don't see an ACT scale, so I don't know what to say about that. Perhaps Bill can enlighten us. Link to comment Share on other sites More sharing options...
mp470 Posted April 2, 2018 Author Share Posted April 2, 2018 You still need Bill, but at -5C it looks like the ECT should have been about 70k ohms instead of 124k. That's way out of range, but I don't think it would cause a huge problem since all that tells the computer is that it is REALLY cold out - like about -50 C. But the engine should still start and run. The real question is what the ECT resistance is when the coolant is up around 80 degrees C or 180 F. But I don't see an ACT scale, so I don't know what to say about that. Perhaps Bill can enlighten us. ACT and ECT should be identical sensors in every way if I'm not mistaken. Link to comment Share on other sites More sharing options...
Gary Lewis Posted April 2, 2018 Share Posted April 2, 2018 ACT and ECT should be identical sensors in every way if I'm not mistaken. That being the case, they both look to be way off. But it is hard to believe they can both be that far off and yet so close together. Can you pull one of them and take it inside to check it at a much warmer temp? Link to comment Share on other sites More sharing options...
85lebaront2 Posted April 2, 2018 Share Posted April 2, 2018 That being the case, they both look to be way off. But it is hard to believe they can both be that far off and yet so close together. Can you pull one of them and take it inside to check it at a much warmer temp? I would try the ACT as it won't leak water if it is removed, yes they apparently are the same since the value charts are the same. Link to comment Share on other sites More sharing options...
mp470 Posted April 4, 2018 Author Share Posted April 4, 2018 I would try the ACT as it won't leak water if it is removed, yes they apparently are the same since the value charts are the same. Out came the ACT. It's carboned up pretty bad but appears to be original. Part E4AF-12A697-AA embossed on the connector. Even with the carbon, readings appear to be right on the money with warm temperatures from 20-100C and smooth transitions in between. It's soaking in some throttle cleaner for a bit, then may put it in the freezer to measure cold. The ECT will be much easier to remove, hopefully doesn't lose much coolant - i don't think it will. Link to comment Share on other sites More sharing options...
Gary Lewis Posted April 4, 2018 Share Posted April 4, 2018 Out came the ACT. It's carboned up pretty bad but appears to be original. Part E4AF-12A697-AA embossed on the connector. Even with the carbon, readings appear to be right on the money with warm temperatures from 20-100C and smooth transitions in between. It's soaking in some throttle cleaner for a bit, then may put it in the freezer to measure cold. The ECT will be much easier to remove, hopefully doesn't lose much coolant - i don't think it will. That is the right number for the air charge temp sensor. Used on a whole lot of trucks. Link to comment Share on other sites More sharing options...
mp470 Posted April 21, 2018 Author Share Posted April 21, 2018 That is the right number for the air charge temp sensor. Used on a whole lot of trucks. Well, I believe my issue is resolved (at least this one). The idle screw was out way too far, I feel like an idiot. I'm still a bit confused as to why it would start fine cold but not hot though. In any case, it's fixed. Thank you all for the help. I was able to finally do a proper KOER test and the codes are 41 and 34. I tested the EVP and it gets 5V and the resistance is around 4000 ohms at rest and 500 with the sensor solenoid(?) fully pressed in (I removed the EVP from the valve for this test). It fluctuates smoothly. Haynes manual says 5000 at rest and 100 with 20inHg of vacuum. Waiting for pump in the mail. The only strange thing is that there is no vacuum going into (or coming from) the green line attached to the EGR valve. The line itself is intact all the way to the assembly that controls the vacuum at which there is none either. Need some guidance on this possibly. The O2 sensor, I will have to locate later so I can do testing on it. I take it the access is from underneath. Link to comment Share on other sites More sharing options...
Gary Lewis Posted April 22, 2018 Share Posted April 22, 2018 Well, I believe my issue is resolved (at least this one). The idle screw was out way too far, I feel like an idiot. I'm still a bit confused as to why it would start fine cold but not hot though. In any case, it's fixed. Thank you all for the help. I was able to finally do a proper KOER test and the codes are 41 and 34. I tested the EVP and it gets 5V and the resistance is around 4000 ohms at rest and 500 with the sensor solenoid(?) fully pressed in (I removed the EVP from the valve for this test). It fluctuates smoothly. Haynes manual says 5000 at rest and 100 with 20inHg of vacuum. Waiting for pump in the mail. The only strange thing is that there is no vacuum going into (or coming from) the green line attached to the EGR valve. The line itself is intact all the way to the assembly that controls the vacuum at which there is none either. Need some guidance on this possibly. The O2 sensor, I will have to locate later so I can do testing on it. I take it the access is from underneath. Peeling the onion! One layer down - how many to go? The codes you are getting are as follows, from this page, with O = Key on Engine Off (KOEO), R = Key on Engine Running (KOER), and C = Continous Memory: 41 R Injectors out of balance on 5.0L SEFI; EGO sensor voltage low (except 5.0L SEFI) 34 O,R,C Canister or EGR valve control circuit or EVP voltage high So, you will have to check out the O2 (EGO) sensor. And coming from underneath is the way to do that. Link to comment Share on other sites More sharing options...
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