91 ranger hit hole in road now runs HORRIBLE if it starts....!!!

[Killtime8]

First off would like to start and say thanks for all the help with my previous thread a few months back. I got the problem worked out, turns out it was a "weak" fuel pump. Anyhow while driving today to get a part for A DIFFERENT vehicle, which is broken down, I hit a hug hole, open manhole cover, a cow or something in the road; It was a hole but just wanted to describe the well kept county rounds we have here in NC. I hit the hole right before I took a left to get onto the highway onramp and the truck jumped back and forth violently (obviously). After taking my left the truck started to jerk back and forth and trying to die. My first thought my was the connectors for my fuel pump had come loose, since I have dealt with so many fuel pump problems it was my first thought. It then dies completely on the side of the road and I turn the key over and the fuel pump is cutting on. I have:

-Fuel at the fuel filter, before and after
-Fuel at the rail, gas shoots out when I press in the valve up top

After letting it sit for a second while I checked all this, the truck started back up again. It BOGS down HEAVY under wide open throttle and you have to feather it to even get it to rev a little. SOMETIMES it will allow you to feather it to say 3-4 grand and you can hold it there and seems to run fine, but it you WOT it bog back down and hover at 1k RPM. letting off it will do its little chug chug chug then slowly die. Try to crank it right after it starts for a split second then dies again and the starter does that long high pitch whine noise. Letting it sit for a minute or 2 it will start again but same things happen. Rinse and repeat.....

Haven't check for spark yet but I assume its getting spark since it will fire sometimes and idle for a little bit before dying again. So...

-I'm getting fuel at the rail
-Seem to be getting spark

Could I have jumped timing hitting the hole? maybe a loose ground? I ripped the computer out from the passenger side floorboard and checked all the connections and "lightly" tapped it a few times. Still nothing.

Any help would be GREATLY appreciated guys, love the site!!!

 

[Killtime8]

Forgot....
145k miles
4x2

 

[Killtime8]

Now I just started the truck up (cold) and it runs just fine...didn't drive it though... I didn't want it to die once it warmed up or something and have to use 2 AAA tows in one day. Just not sometime I ever wanna check off the bucket list...having to be towed twice in a day

 

[Killtime8]

Replaced ICM and still nothing... noticed dist. getting hot on the backside.....

 

[alwaysFlOoReD]

Have you check the fuel pressure? I had a similar problem, it ended up being the short 2"hose split between the new pump and level sender assembly. It would only push 20 psi instead of the forty it should get.

Richard

 

[2813josh]

To me it kinda sounds like MAF.....like maybe your air cleaner came loose or the tube cracked. That's what happened on my explorer.
I hit a good bump and it started running shitty. Unplugged the MAF and it ran ok. Turns out the tube cracked right before the throttle body so it was getting unmetered air and leaning out. Ran horrible until I got a new air intake tube.

 

[2813josh]

Also, yes definitely chec your ground straps..possible one came loose or even snapped.

 

[Killtime8]

My ranger is a 90 2.9 it doesn't have a maf, I think its speed density. It has map sensors. Josh where would the ground straps be? I've check the cables coming off of the negative from the battery cable and they just run into the main harness along the ps fender and go up into the firewall into the cab into the computer. I REALLY don't want to kick another dent into it lol.