2.9 rough idle and weird power loss

[Nathan123]

Hey guys you may remember twoo weeks ago I had the run around with replacing my fuel pump and filter, and repairing the line. Well just this friday I came home from school and when I started hitting a lot of stop signs, every now and then it would stall. Also, just starting friday, it would take 2-3 tries with the starter to get it to fire. So I did some research, got a fuel pressure gauge and had a 100 psi gauge maxed out when running. Then I replaced the fuel pressure regulator (100 bucks) and now the starting issue is cleared up. However, it still maintains a pulsing or surging idle like from 900 to 1000 rpms. Standing in front of the exhaust it sound like it has a hot cam in it. Now, driving back to college, occasionally, especially on hills, I have to put the gas to the floor and it doesn't want to rev much past 3 grand. Sometimes it goes to 3300 then actually drops down to 3000 and really feels to bog down. Other times it willl be just fine. IAC was new last year. Air filter is 2 weeks old. new fuel pump, filter, and FPR. I cannot detect any obvious vacuum leaks. Any ideas

 

[jrpdash9]

my friend had a 1990 ranger with a 2.9 it did the same thing.... now both happened at one time... the fuel reg went and the oil pump went... he had a bad loose of power and it barly idled..(yes we drove it home =)) we replaced the oil pump and good as new.... idk if that helps or not

 

[Nathan123]

well that's not good news but my oil pressure gauge does show normal like it always has, not that I have a lot of faith in the gauge.

 

[bfiakas]

Take a reading on the computer codes and check the ICA,MAP sensor and calibrate the TPS and also recheck your baseline igntion timing and make sure it advances with the spout plug reinstalled.And do a vacuum test for a pluged exhaust sys,

 

[Nathan123]

Well, I've checked the codes and got nothing. The exhaust shouldn't be plugged because it is only about 3 months old. I'm not sure about the other sensors but reading through some other posts made me think about the TPS and how to calibrate it. The black cover that goes over the throttle linkage was being held on by zip ties...someone obviously messed with it before. Just need the chance to put a good multimeter on it and see where it is. The post I read said it should read .92-.95 volts with the key on engine off and the throttle closed (at idle position). Is this correct?

 

[kbold]

check for vacuum leaks, on my 2.9 1 vacuum leak made it sound like it was cammed and made it miss so bad it shook the whole truck.

 

[Nathan123]

Kbold, where was the vaccum leak on your truck? I did adjust the TPS to within specs and it seems to run better. I havn't had a chance to drive it that much but I will maybe today or tomorrow. I'm still puzzled by the loss of power on hills though. We'll see what happens.