87 Ranger w/2.9 Flooding

[criley]

My son has an 87 Ranger w/2.9L V6 that will only start with the throtlle about half open then spews black smoke until gas runs out the tailpipe. It has brand new tune-up parts, new O2 sensor, new engine computer, and new fuel pressure regulator. Codes are very erratic but center around ACT and Coolant temp sensors or the idle air control and EGR valve. Truck won't run long enough to warm up so I fear some of those codes are erroneous. I have also checked the intake for loose bolts and there were none more than 1/4 turn loose. Can't find a vacuum leak, but again can't keep it running long enough to do much. Sorry for the long post, but I need help!

 

[criley]

I can't believe that no one has any suggestions. I have read 55 pages of posts and got some good ideas, but where do I go from here?

 

[jeepshop]

A bad coolant temp sensor could be your cause. Back in those days Ford put heavy emphises on the coolant temp sensor, even more so than the O2. If it's out of range then the ECM could think the engine is very cold. On the other hand, if you run a scan on a cold engine, you will always get a code for the air and coolant temp sensors. I would still suspect a bad fuel pres regulator, pull the vacume line off several times, sometimes it take a dozen or so trys, but then all of a sudden there is gas in the vacume hose. That's another point, what is the fuel pres? If it is way too low the ECM will open up the pulse width on the injectors untill it gets the amount of fuel it wants. If pres is too low the the injectors are wide open, and the spray pattern goes to pot. One last thing, the Ford EECIV routed the fuel control through the distributer module. I've seen bad modules and pickup coils do some really very strange things, but still manage to run. Just for grins after all else here has been checked you might want to throw in a module, I've seen it cure a lot of problems other than spark control.

 

[criley]

Thanks jeepshop. Pulled the vacuum line several times like you said and sure enough the brand new fuel pressure regulator was bad. Runs now, but still is rich especially at idle. Bench tests on the sensors doesn't prove anything I will commit to. I am going to replace the new spark plugs now, figure they are ruined from being flooded so much.

 

[Tbars4]

just a thought...as you mentioned a new computer??? is it brand new or used...is it for your exact year or a newer year???...and was the computer and fuel pressure regulator both changed before this problem appeared???

 

[jeepshop]

If the engine ran terribly rich for a while it could have fouled the O2. I recommend changing the oil and filter as the oil is most likely full of raw gas. Then warm the engine up and while holding it at about 2,000 remove the vacume line to the power brakes creating a big vacume leak. Hold the rpm's around 2,000 for 1 min, then reconnect the hose and drop rpm's back to idle. Now how does it run?

 

[criley]

tbars4...Remanufactured computer and new regulator (X2) from parts store. Both were replaced due to problems listed.

jeepshop...Just got home from work. I will try your suggestion and get back with you.

Thanks!

 

[Tbars4]

damn, that is a problem....i am just wondering too if you were to disconect your battery also to remove its memory of this previous running condition if you haven't...just a suggestion as sometimes it's the little things that we sometimes forget, lol