My 5.0L misses?

scooter · Sep 26, 2010

86 5.0L in my BII is Missing and lacking bottom end power. If I keep the rpm above 2000 it stays cleaned out and does ok, but if I idle around crawling it seems to load up, you can even smeel its running rich... It seems to do it worse at operating tempthan it does when its still "cold".
Fuel pressure is great, plugs and wires are good, cap and rotor should be good.

Injectors crapping out? I am just outa ideas.

Any Ideas, suggestions?

THANKS, Todd S.

originalnitro · Sep 26, 2010

Is the computer from same vehcle as the motor?

Iron Ranger · Sep 26, 2010

Did it just start doing it or has it been doing it since you swapped motors?

kimcrwbr1 · Sep 26, 2010

Pull the codes sounds like a 0-2 sensor or possibly a vacuum leak. If the engine coolant temp sensor is not telling the computer it is warm it will run rich that could be why it runs better cold. Let us know what you figure out.

scooter · Sep 27, 2010

originalnitro said:
Is the computer from same vehcle as the motor?

No, but wireing harness, injectors,maf,intake,ect is from the same car.. A 1989 crown vic. "Bottom end" is out of a 86 crown vic. It was Speed dencity, swapped over to MAF with all new stuff.

Iron Ranger said:
Did it just start doing it or has it been doing it since you swapped motors?

Started about a year ago, but now WAY more noticeable since the axle, tire swap.

kimcrwbr1 said:
Pull the codes sounds like a 0-2 sensor or possibly a vacuum leak. If the engine coolant temp sensor is not telling the computer it is warm it will run rich that could be why it runs better cold. Let us know what you figure out.

I lost my code reader, I am trying to find it...... I dont think its vacuum, it idles really low. I can unhook a vacuum line and it idles up allot.

Thanks, Todd S.

kimcrwbr1 · Sep 27, 2010

All you need is a test light or a volt ohm meter to pull the codes.

http://www.therangerstation.com/tech_library/OBD_I.html

here is the link to the tech library does that have the EEC-IV emissions.

cammeddrz · Sep 27, 2010

i had a buddy tell me the same thing bout his 5.0 how it lacked power, spit raw fuel from the pipes, missed until he revved it up.......turns out he had the plug wires set up for a 5.0 when his cam needed the h.o./351w firing order. so 2 wires were switched don't know if this helps

scooter · Sep 27, 2010

kimcrwbr1 said:
All you need is a test light or a volt ohm meter to pull the codes.

http://www.therangerstation.com/tech_library/OBD_I.html

here is the link to the tech library does that have the EEC-IV emissions.

Man, I forgot you can even do that ! ! ! ! Ill do that right quick and post results.

scooter · Sep 27, 2010

cammeddrz said:
i had a buddy tell me the same thing bout his 5.0 how it lacked power, spit raw fuel from the pipes, missed until he revved it up.......turns out he had the plug wires set up for a 5.0 when his cam needed the h.o./351w firing order. so 2 wires were switched don't know if this helps

When I first built it, Oriellys gave me the H.O. firing order and it did not like it.....

It dosent always do it. thats what confuses me.

cammeddrz · Sep 27, 2010

intermittent huh? it wouldn't happen to do this when the truck is warm or hot would it?

scooter · Sep 27, 2010

Ok, here we go....

23- TPS set to high. I was screwing with it not long ago, prolly me screwed it up. Ill unhook battery for a while and try again.

67- Park/Netrual falt. Duh, never hooked that crap up....

81- Boost Control solenoid. I have no idea I had a turbo.lol

82- AIRB Solenoid. Never heard of that, what the hell is it?

84- EGR, yea that crap is all missing too.

85- CAMP Solenoid. Got me here too, never heard of it.?.?.?

Thanks again, Todd S.

scooter · Sep 27, 2010

cammeddrz said:
intermittent huh? it wouldn't happen to do this when the truck is warm or hot would it?

Yea, read first post. " worse when the engine is at operating temp". :thefinger:

Teddyzee · Sep 27, 2010

81 (TAB) 82 (TAD) 84 and 85 (Cannister purge [charcoal vent]) are all emmisions stuff, no effect on driveability.

67 will only affect idle (usually a rolling or high idle). This is cured by jumping pin 30 and 46 together. In a Mustang, this happens on the T5 or auto trans. Not applicable on a Ranger, as they had no manual trans neutral switch. This is wired in parallel with the clutch switch, so this code doesn't show if the clutch in pushed in (if it's wired up). This is different circuits than the clutch pedal starter interrupt. I've jumped two wires in the clutch switch together to eliminate code 67. Again, not eliminating the start function.

This article shows the basics of reseting the TPS.
http://sbftech.com/index.php/topic,1031.0.html
It's simple, key on, set the voltage to somewhere less than 1 volt. (.9something). Stick the voltmeter probes through the green and black wires on the sensor itself.

See if resetting it helps anything.

scooter · Sep 27, 2010

Teddyzee said:
81 (TAB) 82 (TAD) 84 and 85 (Cannister purge [charcoal vent]) are all emmisions stuff, no effect on driveability.

67 will only affect idle (usually a rolling or high idle). This is cured by jumping pin 30 and 46 together. In a Mustang, this happens on the T5 or auto trans. Not applicable on a Ranger, as they had no manual trans neutral switch. This is wired in parallel with the clutch switch, so this code doesn't show if the clutch in pushed in (if it's wired up). This is different circuits than the clutch pedal starter interrupt. I've jumped two wires in the clutch switch together to eliminate code 67. Again, not eliminating the start function.

This article shows the basics of reseting the TPS.
http://sbftech.com/index.php/topic,1031.0.html
It's simple, key on, set the voltage to somewhere less than 1 volt. (.9something). Stick the voltmeter probes through the green and black wires on the sensor itself.

See if resetting it helps anything.

Yes on 67.... I have the "rolling" or "surging" idle. I will jump those wires together.

I just read about setting up the TPS, so I will give that a whirll tomorow.

THANKS for all the help.
Todd S.

scooter · Oct 11, 2010

Ok, I jumped 30-46 together, and no difference. Runs great cold, but starts missing and loosing ALLOT of power when it gets hot....

I put on a new fuel filter, just in case, no change. Oem filter, not some odd, aftermarket, its the stock filter.

I have an extra Distributer, shoud I try it.?.?.?

Fuel injectors getting hot and leaking.?.?.?

ECM getting hot.?.?.?
I will pull the codes right now and see what I get. I had the puter unplugged for about 20 minutes saturday, so it will be all new data.

THANKS, Todd S.

My 5.0L misses?

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