Fixing a old F150
12-15-2015, 06:26 PM
#1
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Fixing a old F150
I have been slowly getting the 1990 4.9L F150 I got back on the road. I have a emissions/vehicle inspection arranged. BUT I pulled codes from this truck which after starting you need to keep pressing the throttle or else it stalls. After a while it will idle fine on its own. The codes I got.
Cold KOEO
21 Engine Coolant Temperature sensor out of range
24 Intake air temperature sensor out of range
26 Transmission oil temperature sensor out of range. Since the other part of code 26 is about MAF and my truck has a MAP
After driving around the block a little to warm it up.
KOEO 11 System OK
KOER
41 System lean
33 EGR did not open/respond during test
25 Knock sensor not tested
I enjoy working with electronics and sensor's but when it comes to all this I am stumped on where to start first. Does anyone have any idea's?
Cold KOEO
21 Engine Coolant Temperature sensor out of range
24 Intake air temperature sensor out of range
26 Transmission oil temperature sensor out of range. Since the other part of code 26 is about MAF and my truck has a MAP
After driving around the block a little to warm it up.
KOEO 11 System OK
KOER
41 System lean
33 EGR did not open/respond during test
25 Knock sensor not tested
I enjoy working with electronics and sensor's but when it comes to all this I am stumped on where to start first. Does anyone have any idea's?
Last edited by OldFordTruck; 12-15-2015 at 11:21 PM.
12-15-2015, 08:34 PM
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Already ordered one earlier today along with a OBD1 scanner. I got tired of making my light flash with a paper clip. Go to write a number and you can end up missing a flash
12-15-2015, 08:51 PM
#4
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Towards the idle issue - this generation was notorious for fouling the IAC solenoid with gunk - suggest to take it off and clean with carb cleaner so the piston moves freely.
If the EGR valve moves when vacuum is applied, then it's usually the sensor on top of the valve - there were at least two different sensors used, be sure to get the right one, usually indicated by color, if you choose to replace. To a much lesser extent, the vacuum control solenoid supplying vacuum to the valve has been known to clog up and fail - just trace the vacuum hose back to the solenoid.
If the EGR valve moves when vacuum is applied, then it's usually the sensor on top of the valve - there were at least two different sensors used, be sure to get the right one, usually indicated by color, if you choose to replace. To a much lesser extent, the vacuum control solenoid supplying vacuum to the valve has been known to clog up and fail - just trace the vacuum hose back to the solenoid.
12-16-2015, 05:14 PM
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Well I was looking around today and noticed the EGR doesn't have a hose on it going to the EVR on the routing diagram. My Haynes manual should get here tomorrow. When I look at the routing diagram for the vacuum hoses I can hardly see what says what due to where it is located under the hood. I can see the obvious hoses that are on top of the intake.
12-17-2015, 10:16 AM
#7
