Wesley Posted December 27, 2020 Author Share Posted December 27, 2020 If you have an evap code it may well be a vacuum leak. But I think you should check into why you're getting a code for 'idle too low' when it's really too high. Would a TPS out of adjustment cause this? Wait maybe not as it would be reading the RPM from the IGN system right? Never mind me I don't know what I talk about That is why my truck dose not have a computer, I make all the adjustments. Dave ---- I've got a CD with the shop manual on its way for my truck, but a quick search on a Code 13 indicates I should check for a vacuum leak and then the air bypass valve. Need to pick up a propane torch for that. I replaced the IAC and TPS on the first go-round (10-odd years ago) but who knows what sitting might have done. Link to comment Share on other sites More sharing options...
Wesley Posted December 27, 2020 Author Share Posted December 27, 2020 I've got a CD with the shop manual on its way for my truck, but a quick search on a Code 13 indicates I should check for a vacuum leak and then the air bypass valve. Need to pick up a propane torch for that. I replaced the IAC and TPS on the first go-round (10-odd years ago) but who knows what sitting might have done. Quick clarification -- the Chilton guide indicates a Code 13 actually means the engine couldn't reach its lower RPM limit, NOT that the RPMs are too low. So at least I'm not imagining things. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted December 27, 2020 Share Posted December 27, 2020 Quick clarification -- the Chilton guide indicates a Code 13 actually means the engine couldn't reach its lower RPM limit, NOT that the RPMs are too low. So at least I'm not imagining things. Ok. But that would suggest that the computer doesn't recognize the actual rpm's. I understand that V-8 tachs need to be grounded and I-6 engines not. Perhaps the issue starts there? Link to comment Share on other sites More sharing options...
Wesley Posted December 27, 2020 Author Share Posted December 27, 2020 Ok. But that would suggest that the computer doesn't recognize the actual rpm's. I understand that V-8 tachs need to be grounded and I-6 engines not. Perhaps the issue starts there? My F-150 didn't come with a tachometer, but I'd assume the electronics are all there? Link to comment Share on other sites More sharing options...
Wesley Posted December 28, 2020 Author Share Posted December 28, 2020 My F-150 didn't come with a tachometer, but I'd assume the electronics are all there? Belts replaced today, and it turns out my ears aren't as reliable as I thought. Tested for vacuum leaks and didn't find any, then recorded and analyzed audio of my engine at idle. If I did it correctly, I'm estimating an idle RPM in the neighborhood of 600. The idle seems to have stabilized too. Still throwing those codes though, and I would like to try to resolve them soon-ish. To be continued. Link to comment Share on other sites More sharing options...
Gary Lewis Posted December 28, 2020 Share Posted December 28, 2020 My F-150 didn't come with a tachometer, but I'd assume the electronics are all there? Electronics no. Wiring yes. Trucks w/o gauges, meaning those with idiot lights, didn't have the wiring for a tach. But in '86 Ford dropped the idiot lights, so you should have gauges and the wiring should be there. You just need the tach and, maybe, the flex circuit on the back of the gauges. Link to comment Share on other sites More sharing options...
Wesley Posted January 2, 2021 Author Share Posted January 2, 2021 Belts replaced today, and it turns out my ears aren't as reliable as I thought. Tested for vacuum leaks and didn't find any, then recorded and analyzed audio of my engine at idle. If I did it correctly, I'm estimating an idle RPM in the neighborhood of 600. The idle seems to have stabilized too. Still throwing those codes though, and I would like to try to resolve them soon-ish. To be continued. Hoses, thermostat, front brake pads, wiper blades replaced. Cleaned the air filter (K&N). Truck is overheating, and since the fan is running I suspect it's the water pump? No coolant leak. The idle issue seems to have resolved itself. Reset the computer, so I'll try pulling codes again and see if they're still there. A few more odds and ends should make it driveable. Link to comment Share on other sites More sharing options...
FuzzFace2 Posted January 2, 2021 Share Posted January 2, 2021 Hoses, thermostat, front brake pads, wiper blades replaced. Cleaned the air filter (K&N). Truck is overheating, and since the fan is running I suspect it's the water pump? No coolant leak. The idle issue seems to have resolved itself. Reset the computer, so I'll try pulling codes again and see if they're still there. A few more odds and ends should make it driveable. Keep plugging away and before you know it it will be done. How do you know it is over heating? Dash gauge or after market gauge or temp gun to get temps and if so from where? Dave ---- Link to comment Share on other sites More sharing options...
Wesley Posted January 2, 2021 Author Share Posted January 2, 2021 Keep plugging away and before you know it it will be done. How do you know it is over heating? Dash gauge or after market gauge or temp gun to get temps and if so from where? Dave ---- Aftermarket gauge I installed when the dash gauge failed. After replacing the thermostat and coolant I started it up and the temp was holding steady at about 190. Drove it around the neighborhood and it rose steadily up to 220-230 before I got it back. Link to comment Share on other sites More sharing options...
old55pete Posted January 2, 2021 Share Posted January 2, 2021 Aftermarket gauge I installed when the dash gauge failed. After replacing the thermostat and coolant I started it up and the temp was holding steady at about 190. Drove it around the neighborhood and it rose steadily up to 220-230 before I got it back. With the engine running, take off the raidator cap. After the engine comes up to temp, you should be able to see the coolant flowing out of the end of the tubes. I have seen a radiator plug with coolant in the past. The test I am giving will only tell you it you have flow, thats all. The thermostat being in backwards will also make it not flow. All I am saying is do some testing before you start changing parts. Link to comment Share on other sites More sharing options...
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