Im posting this in my build thread as well but figured this might help some other people with issues so i made a topic here...
Ok so after my build ive had this annoying "pop" backfire at low rpms after the car backfired it would pull hard. Since i moved i havent really looked in to the issue the car has just sat garaged at my parents.
I was also having issues with my tune and AFRS and i attributed this to my tune.
However i think i had it backward.
Some back story:
car backfires and clears out and runs fine after at high rpms
Failed Emissions for high HC's
Reading lean/fluctuation on wideband (thought this might be because of my huge primaries)
When i bought my injectors 24lbers (used) i was given 9... one in a bag which i told had a crushed cap.
I figured i had unburnt fuel getting in from somewhere causing this issue... i thought it was in the tune. However determined to find the issue i borrowed my friend chris' IR thermometer.
I hit each of the 1 3/4'' primaries on my accufab headers at idle starting on the side with the wideband.
5: 700-740
6: 700-740
7: 700-740
8: Mid 600's
Low temps would indicate a possible rich condition i guess... While higher a lean condition.
I thought that was odd to see 100 degree lower temps so i checked the plug wire. 2ohms... i checked the plugs (only a few hundred miles) 8 looked slightly darker than 4 no huge difference though.
I checked the cap... found a burnt spot on a different plug.
So i changed the cap and rotor out and took it for a spin... More backfires.....
Chris had an extra set of 24lb injectors from his cobra sitting in the attic he let me have
So i decided to pull the manifold and look at the fuel injectors maybe one of these had the crushed cap and somewhere something got mixed up...
I pull the manifold and take the injectors out of port 8.... Then out of 5,6, and 7.
Oh no... one of these things is not like the others!
All the ones on the car matched the left 4 port spray pattern while the lonely injector on port 8 had the single style ford pintle (which im assuming was leading to a rich condition and lower temps)...
So a ford style injector was mistakenly sent to the previous owner to replace a 4 port spray patten...
Well good new is i may have found my problem. I swapped the injectors over to chris' cobra (ford) single pintle injectors ill have the manifold back on in the am. Lets hope this fixes the issue. The IR thermometer is possibly my new favorite tool.
Ok so after my build ive had this annoying "pop" backfire at low rpms after the car backfired it would pull hard. Since i moved i havent really looked in to the issue the car has just sat garaged at my parents.
I was also having issues with my tune and AFRS and i attributed this to my tune.
However i think i had it backward.
Some back story:
car backfires and clears out and runs fine after at high rpms
Failed Emissions for high HC's
Reading lean/fluctuation on wideband (thought this might be because of my huge primaries)
When i bought my injectors 24lbers (used) i was given 9... one in a bag which i told had a crushed cap.
I figured i had unburnt fuel getting in from somewhere causing this issue... i thought it was in the tune. However determined to find the issue i borrowed my friend chris' IR thermometer.
I hit each of the 1 3/4'' primaries on my accufab headers at idle starting on the side with the wideband.
5: 700-740
6: 700-740
7: 700-740
8: Mid 600's
Low temps would indicate a possible rich condition i guess... While higher a lean condition.
I thought that was odd to see 100 degree lower temps so i checked the plug wire. 2ohms... i checked the plugs (only a few hundred miles) 8 looked slightly darker than 4 no huge difference though.
I checked the cap... found a burnt spot on a different plug.
So i changed the cap and rotor out and took it for a spin... More backfires.....
Chris had an extra set of 24lb injectors from his cobra sitting in the attic he let me have
So i decided to pull the manifold and look at the fuel injectors maybe one of these had the crushed cap and somewhere something got mixed up...
I pull the manifold and take the injectors out of port 8.... Then out of 5,6, and 7.
Oh no... one of these things is not like the others!
All the ones on the car matched the left 4 port spray pattern while the lonely injector on port 8 had the single style ford pintle (which im assuming was leading to a rich condition and lower temps)...
So a ford style injector was mistakenly sent to the previous owner to replace a 4 port spray patten...
Well good new is i may have found my problem. I swapped the injectors over to chris' cobra (ford) single pintle injectors ill have the manifold back on in the am. Lets hope this fixes the issue. The IR thermometer is possibly my new favorite tool.
