MAP Sensor???? Running Lean???
02-21-2011, 11:38 AM
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MAP Sensor???? Running Lean???
My 1987 F150 is having issues when running under a load. AT about 45-50 mph or going up hill, the engine sputters and lurches as if it is not getting enough fuel. At first I thought this lean condition was caused by a clogged fuel filter or bad gas, but after changing the filter, cleaning the injectors, and filling up with new gas, nothing has worked. I suspect it may be caused by a fouled Mass Airflow sensor. Any idea if I may be on the right track?
I have the v6 engine.
Thanks
I have the v6 engine.
Thanks
Last edited by bowie1; 02-21-2011 at 11:47 AM.
02-21-2011, 12:27 PM
#2
Hi-Rev Motorsports
no V6 in 87 for the 150 pick up....
if its lean and you know it is then check fuel pressure under load...the MAP will NOT make it run lean as under load there is less vacuum and that makes it run rich unless the map is real bad andf by then it just wont run or idle either...if it idles fine then in most cases the MAP is good and the problem is elsewhere...
for fuel being lean it will be the O2 sensor or the fuel system...
if its lean and you know it is then check fuel pressure under load...the MAP will NOT make it run lean as under load there is less vacuum and that makes it run rich unless the map is real bad andf by then it just wont run or idle either...if it idles fine then in most cases the MAP is good and the problem is elsewhere...
for fuel being lean it will be the O2 sensor or the fuel system...
02-21-2011, 01:05 PM
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My 1987 F150 is having issues when running under a load. AT about 45-50 mph or going up hill, the engine sputters and lurches as if it is not getting enough fuel. At first I thought this lean condition was caused by a clogged fuel filter or bad gas, but after changing the filter, cleaning the injectors, and filling up with new gas, nothing has worked. I suspect it may be caused by a fouled Mass Airflow sensor. Any idea if I may be on the right track?
I have the v6 engine.
Thanks
I have the v6 engine.
Thanks
02-22-2011, 09:51 AM
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no V6 in 87 for the 150 pick up....
if its lean and you know it is then check fuel pressure under load...the MAP will NOT make it run lean as under load there is less vacuum and that makes it run rich unless the map is real bad andf by then it just wont run or idle either...if it idles fine then in most cases the MAP is good and the problem is elsewhere...
for fuel being lean it will be the O2 sensor or the fuel system...
if its lean and you know it is then check fuel pressure under load...the MAP will NOT make it run lean as under load there is less vacuum and that makes it run rich unless the map is real bad andf by then it just wont run or idle either...if it idles fine then in most cases the MAP is good and the problem is elsewhere...
for fuel being lean it will be the O2 sensor or the fuel system...
02-22-2011, 10:35 AM
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Any ideas on how to test to see if "what" is the issue?
Run error code scans.
https://www.f150forum.com/f10/how-re...es-obdi-10907/
OR
http://www.handsontools.com/Equus-In...ol_p_5574.html
(you can find them in stores locally for a little closer to $30.)
Last edited by ymeski56; 02-22-2011 at 10:50 AM.
02-22-2011, 10:49 AM
#6
Administrator
EDIT- I fixed the title. If that's not what you meant for it to say, let me know and I'll change it back. I don't think you meant for it to say "MAD sensor", didja?
