Natedog
New Member
- Joined
- Aug 7, 2007
- Messages
- 917
- Reaction score
- 5
- Points
- 0
- Location
- CA
- Vehicle Year
- 87
- Make / Model
- Ranger
- Transmission
- Manual
I've been having pinging (detonation or pre-ignition) since I got my 87 running with my m5r1 trans. It now has all the 1988 emissions parts on it including the eec unit (eliminates EGR and knock sensor) and it runs alot better but the pinging still occurs. Used the 1987 eec/engine wiring harness though. My pinging starts at about 3500rpm or a bit higher and mostly during medium to heavy throttle. It seemed worse this morning when it was colder (35*F).
Also my idle is kinda rough, plugs look good, and it sometimes does one little tiny backfire when I shift to second gear and accelerate at about 1500rpm....and also sometimes when I decelerate and then re-accelerate at low rpms in second gear.
EDIT: ALways ran 87 octane gas in my other 2.9 and now in this one. This engine was supposedly rebuilt by the previous owner and it looks and feels like it has. Last night I filled the tank with some 89 octane and it didnt' seem to help. Maybe they upped the compression too much and I need 92 octane fuel? I checked at fill up and I'm only getting about 14mpg or a bit less and that seems pretty low considering that I usually drive with light to medium throttle, not flooring it all the time.
What do you suggest?
Also my idle is kinda rough, plugs look good, and it sometimes does one little tiny backfire when I shift to second gear and accelerate at about 1500rpm....and also sometimes when I decelerate and then re-accelerate at low rpms in second gear.
EDIT: ALways ran 87 octane gas in my other 2.9 and now in this one. This engine was supposedly rebuilt by the previous owner and it looks and feels like it has. Last night I filled the tank with some 89 octane and it didnt' seem to help. Maybe they upped the compression too much and I need 92 octane fuel? I checked at fill up and I'm only getting about 14mpg or a bit less and that seems pretty low considering that I usually drive with light to medium throttle, not flooring it all the time.
What do you suggest?
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