93 ranger backfires
 

my 93 ford ranger is backfiring at low idle and slow take off .. high rev and she runs fine
ive changed the plug wires a couple of days ago because of sparking while i looked at the engine at nite time
i changed the fuel filter also a day ago
put on scanner and gave me codes 157 and 116
ive taken care of the truck engine wise
changed oil every 2500 miles
changed timing belt every 60,000 miles
changed plugs every 60,000 miles
has a clean air filter
also have changed fuel pump and injectors
could it be the mafs
or the coil packs
or cam lobes

Check spark plug wires for correct installation.

it was doing it before i changed plug wires as stated in original post
left that part out more help please

More help please? what motor?

2.3 1750000 miles

175000 miles

Is the distributor worn out? Sloppy?

coil packs

2 coil packs eight wires

DISTRIBUTORLESS SYSTEM

ok going to try this again
i am also posting this at the rangerstation.com


This has been doing this for about a month now
At idle and slow take off

Added 4 cans of dry gas in the last 2 weeks
Replaced plug wires because of sparks 5 days ago
Triple checked wires to plugs for correct connections
Replaced fuel filter 3 days ago

Ran a code scanner today after clearing a 116 and a mass airflow sensor code
Got no codes after 2 mile test drive
Also last night i pulled the battery connectors and the {ecm connector}, after the battery so no shorts to ecm

When i put code reader on ranger the temperture guage works when i run koer tests

Still runs rought at idle

I have about 60,000 miles on plugs so i am going to change soon but i pulled them and they are all getting spark from coils and they are tan to grey in uniform color {all plugs}

During the warmup before the testdrive my temperture gauge worked right for the first time in 7 years

I also am still playing with the number 4 plug wire on drivers side just to make sure it seated so i left it off during the warmup
After i hooked up the number 4 wire the temperture dropped down to where it was before

I sprayed carb cleaner and compressed air in the temp gauge connection in the motor compartment and the ecm connection { with battery diconnected}

I have alot of corrosion on alot of engine connection
and have been cleaning all that i have seen for last year

Another question? if i pull the vaccum line off of the egr canister should there be a lot of vaccum i dont feel anything from the cannister or the vaccum line

Still runs rough at idle but not when high revs