91 runs rough

[ashleyroachclip]

I have a 91 ex. had been running poorly for the wife , found the cruise vac, line had come off , ran codes , had a stored memory code for upstream O2 sensor , reattached cruise , cleared codes , and it seemed to be running well again , Except ,,,,,when cold , and starting , it will never start on the first try , crank for 3 seconds , stop re-crank and it will then start , my ranger starts everytime first try.
once it starts it will idle fiine , but if you try to drive off it will sputter , then catch and accelerate fine . Wife also said it is now loosing 10mph up a fair grade while on cruise ,,,,I don't know what the heck is going on , and I have a clean bill f health according to the codes.
Any help would be helpful , I had to order the o2 sensor , 51.00 and since the truck has 187k , I figured it won't hurt to replace it , also picked up an engine coolant temp sensor , was thinking that is may be causing the rich tail pipe I'm seeing .
The wife is ripping me a new one because my truck with 286K runs better than hers ....and I have tolet my oldest son use the truck to go to an IPC concert on monday....

 

[MrShorty]

Question: did repairing the vacuum line resolve the O2 sensor code?

What is fuel pressure doing? Fuel pressured isn't monitored by the computer, so won't always trigger any kind of code. Glacer991 recently wrote a nice little thread that talks a little about testing fuel pressure, if you want to search for it.

 

[ashleyroachclip]

yea the o2 sensor code has not come back , I have not checked fuel preasure , I do have a gauge , and will do so this weekend . Fuel pump has been loud ever since I got this thing over a year ago. My 94 Ranger is quiet , I can just barely hear it running , but the Explorer is another story .

 

[marragtop]

How long has it been since the wires and plugs were replaced?

 

[Billy177]

make sure the maf is clean as well

 

[ashleyroachclip]

new plugs , wires ,fuel filter ,air filter , in the last 6 months .
Replaced the o2 sensor , found a wire that had a bare place , cleaned the maf last fall , and again yesterday, it looked pretty good ...starts better now when cranking , we'll see how it goes , fuel preasure was good ,also cleaned the IAC , and throttle body , we'll see how it goes ...any other suggestions are appreciated .

 

[monkeypothrower]

one of my vac lines came off this morning. I noticed it right away and put it back on but had to tie wrap it to stay on. Mine does the same, i will crank and it will run rough and stutter a little but lay on the rpms a little always seems to help it, then i am fine the rest of the day. Looking this weekend to replace the vac line. -TJ

 

[Billy177]

also pull the vaccum line off the fpr and make sure there is no gas in it

 

[ashleyroachclip]

new fpr less than a year ago , and checked it while checking the fuel preasure ,replaced vacumn line. and rechecked all the rest , also replaced intake gaskets last winter , and one injector that had gone dead , I may just replace all the rest , won't hurt , also replaced pcv. valve at the same time I did the intake gaskets