codes 18,41,34
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codes 18,41,34
My Dad's truck, 86 F150 4x4 302 EFI, has been running pretty rough. Finally got a chance to pull the codes, and came up with continuous code 18, engine running codes 41 & 34. Any ideas on where to start checking? It seems like its flooding itself to death and lacks power. Also, gas mileage has gone to pot. Thought I would get some opinions before I start. Thanks!
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codes 18,41,34
18 tells me to change the coil.
34 says clean the EGR pintle or change the valve or the sender.
41 says test the oxygen sensor & consider replacing it.
If you don't have a Haynes manual, start by buying one.
34 says clean the EGR pintle or change the valve or the sender.
41 says test the oxygen sensor & consider replacing it.
If you don't have a Haynes manual, start by buying one.
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codes 18,41,34
Steve, I have the Haynes manual and it says the code 18 is SPOUT circuit grounded or IDM circuit failure. So, do you think change the coil first and see what happens? Going to clean the EGR tomorrow.
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codes 18,41,34
My book also says that a code 18 is "loss of tach signal" to the computer. This code during the running test indicates there is something wrong with the spout wire. Maybe somebody left it unplugged? It's a yellow/lightgreen wire coming from the dist.
But the book also says that a code 18, although it's perceived to be a spout problem, could also be a problem with the PIP circuit or the TFI module on the dist. Of course the coil is in the mix too, so if it shorted I guess it could pull down the rest of the circuit.
But the book also says that a code 18, although it's perceived to be a spout problem, could also be a problem with the PIP circuit or the TFI module on the dist. Of course the coil is in the mix too, so if it shorted I guess it could pull down the rest of the circuit.
Last edited by Franklin2; Feb 6, 2003 at 11:14 AM.
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codes 18,41,34
Well.....I probed the TACH terminal of the coil with a test light and when I started the truck, the light was bright but did not flash. Proceeded to primary circuit continuity check and the resistance between the coil TACH terminal to ground was 1500 ohms. Manual says reading should be greater than 10,000 ohms. According to Haynes manual I have a short in the harness somewhere. I dread trying to find that. Also, tapped into the SPOUT wire at the ICM and checked voltage-Haynes says it should be between 3 and 8.5 volts. I got 14.7 volts.
Last edited by 87black150; Feb 6, 2003 at 10:04 PM.
