Vehicle:
1987 Ford Ranger 2.3L 4 cyl MT over 200K on it
Issue[s]:
At cold or warm idle the truck idles with a "bub-bub-bub" sound similar to the sound you get if you shift from 2nd to 3rd at low RPMs with any vehicle. You know, that bogged down sound. Only it sounds similar, not exactly like, but similar to low RPM shifting. The truck is starving for something, I just can't figure out what? Hopefully, you can....
Codes:
None current using a digital voltmeter check. Use to show a code 31 EVP/EVR/PFE is out of range or is low. That has since vanished after selling my soul to get a new EGR Valve to replace the old one that was frozen solid with carbon build up.
Along with the new EGR valve, I have replaced:
plugs n wires [didnt need to be changed but figured what the heck]
all new vacuum hoses
O2 sensor, valve cover gasket
throttle body gasket, fuel filter
EGR Position Sensor [my first attempt at the code 31]
i even put a new muffler and tail pipe on because the old ones rusted out

Sensors Checked and cleaned:
MAP
IAC
EGR Solenoid plugs

There is no change to the vehicle at idle when i remove the air charge temp sensor or the EVR solenoid plugs.
However, it will change idle and/or die if i unplug any of the following:
MAP
IAC
or i unplug the hose with vacuum on it from the tree to the EGR solenoid [Red bottom]. BUt, the EGR solenoid test out for proper voltage and does not have vacuum on its top hose [Black] at idle. ??????

The truck just simply has no power when accelerating always acting like i am trying to take off for a dead stop in second gear. If at a stoplight and i take off, by the time i hit 3rd i bet 2-3 cars pass by me. I can be truckin at 45-50 mph in 4th and shift to 5th and the dang thing will act like im shifting too soon and the RPMs are too low. THe truck has no tach, so i've always shifted by feel and sound.

Also, the engine shakes worse than normal at idle and shakes so bad when accelerating that the whole truck shakes.

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1997 Ford Ranger XL 2wd Reg Cab
2.3L 4 cly 57,010 original miles
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1987 Ford Ranger XLT 2wd Reg Cab
2.3L 4 cyl 250xxx miles

I had an 87 that would do the same thing.. I found out the timing belt had stretched and jumped a tooth, causing the cam timing to be off. Replaced timing belt and all was good.

Check timing marks on cam shaft and crank and make sure they are spot on. Thats my 2 cents....

Thanks Blanker, I am going to try that. Just pulled off the cat. converter last night and it was damn near spotless on the inside. So another one crossed off my list.

__________________
1997 Ford Ranger XL 2wd Reg Cab
2.3L 4 cly 57,010 original miles
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1987 Ford Ranger XLT 2wd Reg Cab
2.3L 4 cyl 250xxx miles

how mmuch did you pay for your 87...