Ok. its been a week and after multiple new parts and tweaks I still can't get my 95 sidekick 16v 4dr to run right. It hesitates during driving, kinda bogs for a split second. Its consistant, about every 2-3 secs and lasts about a second. CEL does not come on. Car idles great and the hesitation seems to lessen as it warms up but does not go away entirely. Motor has approx 130k miles.

I have cleaned and or replaced the following:
PCV valve
new valve cover gasket (old was bad)
new plugs
new wires
new cap
new rotor
new fuel filter
checked fuel pressure
checked timing
cleaned MAF
cleaned the TB
cleaned the EGR main valve
Checked and re adjusted the TPS several times

I'm pretty much at a loss here. I will be replacing the O2 sensor later today as well. I need some help guys...

thanks,
-Nick

What was your fuel pressure? you may have to monitor this while driving
to see if there is a fuel pump or regulator problem.

It really sounds fuel related, but it could also be EGR activating when it
should not, also have you checked the spray pattern of the injectors?

MAF installed the right direction, it does matter, and a clean/good air filter

Start eliminating systems, cap off the EGR so no air can get in and drive it,
watch your fuel pressure while driving it, forget about the ignition for now
you replaced all that stuff and it starts, unless it's going retarded but that
would be a computer problem I think on that engine/year

Sorry you are having so much trouble with it
Wild

It would not hurt to do a compression and leakdown test on each cylinder.

Key on, engine off the fuel pressure was about 42psi.

Motor idle the pressure was about 32psi.

4k rpm in nuetral the pressure would spike to 42 psi then fall to 35psi.

This was taken after in line right before the fuel filter.

I will be cleaning the injectors hopefuilly this weekend. How do you check spray pattern?

You need to check the fuel pressure at the fuel rail on the engine, the pressure
should remain a constant 43 PSI, the fluctuation would indicate a bad fuel regulator

To check the spray pattern, you would pull the injectors and activate them for a
short time, like 2-5 seconds while you have fuel pressure feeding the injector, if
you don't have fuel it could fry the injector.

I wouldn't pull and check the injectors until you get the fuel pressure worked out
and running steady, you might also have a sluggish fuel pump in the tank, so
watching your pressure while you are driving will tell you if it is giving you the pressure
you need, and when it's running sluggish, it might just be dropping to lower than the
normal and would be your problem

Wild

So, I took your advice and plugged the vaccum line to the EGR valve. Seemed to work. Truck ran great. Still need to test the fuel pressure at the rail. I will let you know how that turns out but so far so good.

-Nick

Great news, glad to hear you are making progress.

If the surging is gone, you might just want to check the pressure and call it
there.

I wonder did you trace the vacuum hose routing? there could be a miss
connection causing the EGR to open when it's not supposed to

Good work
Wild

would the EGR regulator valve being hooked up backwards cause this? I havent messed with it yet but just curious.

If there are 2 vacuum lines it is a possibility, kind of seems like that's what is going on

Having a the same thing go on with my '95 16V kick. I'll be paying attention here. Also failed local emissions, too (not sure if the two are connected; I have a feeling they are).

- Andy

i too have a '93 with hesitation, almost identicle. talking with brent at TT he says it's either the TPS is bad or the fuel pressure regulator is bad. my 95 started doing it a couple years back, replaced the pressure regulator and it solved the problem. i'm going to start by replacing the TPS since mine did have a CEL on when i bought it and when i ran the code it gave me a code 22. i had my mechanic adjust it to the proper values, but they only set it to hi and low, brent says theres no way of knowing if it's working in between properly.

well, on a whim, i went out this morning and removed the year old fuel pressure regulator from my green rig and put it in my 93 and BAM, it runs like a top!!
time to order another new one for my green one i guess.

A whim, LOL where you been man, I been beating the fuel pressure issue
from the second post, 

Glad you got it fixed tho 

Wild

A whim, LOL where you been man, I been beating the fuel pressure issue
from the second post, 

Glad you got it fixed tho 

Wild

i honestly think the thing has been limping wayyy too long. someone had halfassed the EGR back on(leave the old gasket and just add some sillycone), the cap and rotor were fryed. it's running sooo much better now, but still some very,very slight hesitation. im gonan pick up a fuel filter tomorrow and im thinking it's gonna finish the fix!
i am going to invest in a fuel pressure gauge i think. it makes FI diagnostics a lot easier i think