Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
I have a aussie built? 1990 F150 5 speed 4x4 with a 351 windsor efi OBD1. Its on dual fuel.
Have only just bought it and doing it up. Has had a rough idle and sluggish power that is now time to look at. TPS is 0.9 volts at KOEO and 4 volts at WOT.
Air cleaner new, TB cleaned IAC cleaned with resistance of 9.6 ohms, new leeds and plugs. Running noticeable better after the plugs and leeds thogh still not sound right from that idle and just above. I unplugged the MAP sensor and it idle perfectly so ordered a new senor and installed.
The engine ran terrible would only just idle in a gut full of fuel fashion. Pulled the wires from the new Map and it spluttered and stalled. Needs throttle to keep going re start engine needs throttle Code 22.
Same issue when switched to LPG.
Any advice would be great
Do you have a scanner that can read live data? Can it do koeo self test and koer test?
If yes to all three then start and run engine till warmed up. Then turn off and put key to on position engine off. Do the koeo test. What codes does it give? After that start engine and do koer test. What codes does it give? After tests are done get pics or video of all live data for us this will help narrow down what it is.
Alex
Hi Hardtopdr2 and thanks for your reply.
I have a code reader for the OBD1 system. codes were 22 map senor out of range , 31 egr ,all egr components removed by previous owner and 41 o2 sensor (removed).
put a new map sensor in which made a huge difference to the power/response of the engine, though the idle was terrible and was still as rich as (Eye watering fumes).
reset ? the ecu drove for awhile seemed to be better though idle still bad.
Got hold of a fuel pressure gauge showing 28psi KOEO and about 32psi running.
thinking to change fuel pump and filter. As your videos show always change the filter when doing the pump.
look forward to hearing your thoughts
Thanks
Steven
Also have removed and cleaned the IACV it has 4.9volt supply and 9.6 ohms resistance. The specs are 3 ohms - 7 ohms. Is the 9.6 acceptable or should i replace it?
If iacv is out of spec it will not perform correctly. So yes i would say replace it. Also with the extremely rich condition you will want to check injector flow rate with a pressure drop test and also test the fuel pressure regulator. Fuel pressure on a injected engine should go to 50-60 psi then drop down to rest pressure depending on the regulator ~40-45 psi. Check fuel pressure to see if it holds steady for ten minutes or it it drops quickly. More testing may be necessary if it drops more than 2 psi
