earlyboomer
New Member
- Joined
- Sep 3, 2019
- Messages
- 4
- Reaction score
- 2
- Points
- 3
- Location
- Pennsylvania
- Vehicle Year
- 1986
- Make / Model
- Ford Ranger
- Transmission
- Manual
Hi, I am a new member, and I bought an 86 Ranger 2.9L Rwd truck new in 86 and it has been a hobby since day one. This was the first year for EFI. I read the posts on fuel mileage going south and another where the engine idles poorly. My 2.9L got to the point of not idling very long before it would just quit, unless you were driving it. 2 or 3 years ago I found out about electrolytic capacitors going bad in the Computer (ECU) from a video on YouTube, so I changed them and that one repair changed the engine back to running like a clock. The 4 capacitors are, 3 - .O47 mfd versions and 1 -1 mfd capacitor. These capacitors are the couplers between various Integrated Circuits that control functions like timing advance etc., and when the caps start breaking down they cause problems. They are very small to work with, and to change out, so if you have no electronic experience, maybe you know a buddy that does, and check the videos on youtube. Now I have always used Full synthetic oil in this engine so I never had anything sticking like the lifters. and the engine has stayed clean inside. The engine has 190K on it and around 100K I installed a timing chain set and that really helped. when I had the oil pan off, it was nice and clean. I live in the Rustbelt and among other things it caused the flange between the exhaust header to rust and destroy the seal between the exhaust header and the catalytic converter which caused the manifold pressure signal to the ECU to be off and fixing that helped the running of the engine Any little thing can irritate these ECUs. These items are not in chronological order. They all affect the running and the gas mileage. Like others have said the oxygen sensor is important and another big item for gas mileage is to forget about using the OEM designed muffler. At one point I changed the Injectors at the time when the fuel pressure start leaking gasoline all over the garage and that got my attention. Lately I finally tried the small bottle, 5.5 ounces, of Lucas fuel injector cleaner and was really surprised how well it worked, the engine had a bit more pick up, right away and was instantly noticeable. I have some rust problem with the truck but the engine finally runs like new again. This truck has a 5 speed and one of those awful hydraulic clutches, but the engine does have one pain in the butt problem, those constant leaking valve covers. I made cover supports out of a .75" x .75" x .125" steel angle to go across the whole bottom edge of the valve covers but it didn't cure the problem completely, so I need to put new gaskets in again. When these engines are idling right they have a special sound and replacing the caps in the ECU brought that sound back. Now I get at least 17 to 18 miles per gallon in traffic , keeping up with traffic, and on the few days when the traffic was light and I could keep to the speed limit, I got around 30 miles to the gallon, believe it or not, and it really surprised the H--- out of me, I think a lot of that is because of the turbo muffler with less back pressure. I should have quit using the OEM mufflers years ago. This is a 30 year+ Ranger history lesson, hope some part of it helps someone.