Hesitation problem

[voiddweller]

Hesitations, broken bolts, leaks

So this 95 3.0 4wd I got last month has had its share of issues. The latest that I haven't been able to really figure out is the hesistation. This is what's happening and it's more prevalent when its cold/warming up, but persists throughout the day in some form, always.

1st, 2nd, 3rd gear mostly between 2500-2800 rpm, it goes away the higher the rpm in each gear. When I accelerate in each of these gears its what I can best describe as a studder. It's bad when the engine is warming up but once its been driven for 15-20 min it settles down.

It almost reminds me of my old Nissan that had a crack in the plastic air intake manifold that when the accelerator was pressed, the engine tilted slightly allowing the crack to open and too much air inside, under load.

When I cruise down the backroads 50+ in 4th/5th gear I have no issues with acceleration.

Recently in the last couple days it's gotten worse and I almost feel like it's choking when I accelerate in 1st/2nd gear.

I did the normal plugs, wires, cap, rotor, filters, fluids when I got this beast about a month ago. Fuel filter is new.

I am considering a set of the flamethrowers but before hand thought i'd toss this past anyone and see if they have had the same problem.. Mass air intake sensor or pcv? I'm really not sure.. Hoping its a common problem others have experienced with a simple fix that I'm missing..

Any ideas?

 

[voiddweller]

Also could this be a tps issue? I have a multi meter, found the guide on how to check it however I'm not that confident I am capable of adjusting/testing that.. Looks confusing

If it were one of your vehicles, what process would you go through to fix this?
I'm thinking about cleaning the entire throttle body system, if I do, what would be the best cleaner/solvent?
Do you lube the moving parts with a product or just leave them clean Accelerator cable dry, lubed or graphite powder or something?
Would removing and cleaning the Air Intake Chamber and cleaning the Fuel Injectors be worth the trouble?

 

[Ahlem]

I think you are on the right track with the cracked plastic line. I'd check all the vacuum hoses on the passenger and driver side of the intake plenum to see if something is hissing. You can spray soapy water on the hoses to see if there is any change. Have you put injector cleaner in each tank of gas since you got the car? The TPS isn't too hard to check if you search around for a write up. It did make a big difference in how ours ran. Be sure the timing is set correctly as well. Look for cracks in the intake ducting. I'd wager you have an air leak of some sort. Those old lines get porous.

 

[voiddweller]

I think you are on the right track with the cracked plastic line. I'd check all the vacuum hoses on the passenger and driver side of the intake plenum to see if something is hissing. You can spray soapy water on the hoses to see if there is any change. Have you put injector cleaner in each tank of gas since you got the car? The TPS isn't too hard to check if you search around for a write up. It did make a big difference in how ours ran. Be sure the timing is set correctly as well. Look for cracks in the intake ducting. I'd wager you have an air leak of some sort. Those old lines get porous.

Wouldn't it also be possible that the lesser spray at low rpm from the fuel injectors be affected by dirt/grime/clog, and at higher rpm this issue would be lesser of a problem because of the higher flow rate of fuel coming from them?

 

[mikekfr]

Spray starting fluid/carb cleaner if you suspect a vacuum leak, around any suspected lines, if it revs up, u found your problem. I'd make sure your injectors aren't clogged w/ junk sitting under them, causing a miss when you call for throttle? i dunno man, but good luck to you

 

[voiddweller]

Just went and bought a pile of new vacuum hoses for the top end, going to replace them this evening or tomorrow morning, hopefully it helps.

 

[91'4bee]

Hey man let me know if this fixes it! I have this same issue but only in 2nd gear accelerating slowly or moderately. When at full throttle in 2nd gear I don't notice it but your description matches my symptom and I cant pin point it either. I have checked or changed everything easily accessible but no luck.

 

[Ahlem]

Carb cleaner yes, starting fluid NO. That stuff is way scary when used wrong.
If you can make it miss when revving in Neutral in your driveway, you can check specific cylinders by pulling plug wires. If there is no difference with the wire on or off, I'd suspect a clogged injector in that cylinder, after you check the vacuum.

 

[gtgt_bangbang]

PS ; "Pulling Plug Wires - "

dont forget you can pull wires AT THE DISTRIBUTOR too, and a heck of a lot easier than pulling at the plug

 

[voiddweller]

Thanks Ahlem, great advice, I'll try that tomorrow. Replaced all the vacuum lines and nothing's changed. Starter went out this morning , replacing that thing was a tight squeeze, wow

 

[voiddweller]

Some other issues

I went ahead and replaced all the vacuum lines that I could, replaced my Starter (royal pain) and now I have some other questions, I'll stick to this thread instead of posting a new one. Make note these are probably very newb questions with pics.

Can I clean/test the EGR valve to ensure its operating properly? I've read that if its failing it can cause what appears to be a vacuum leak. Mine appears to be very old looking possibly original.

The Charcoal Canister: How often do these need replacement, can they be cleaned? If mine is original/20 years old, should I replace it no matter what?

I picked up a skid plate in pretty good shape from the parts yard for 20 bucks. I went to see about the bolt-on situation and it appears that the bolts from the previous one were broken off at the head. Now I have 0 experience removing broken bolts, can someone give me advice on this process?




I also picked up the new distributor cap/rotor and when I put the new one on, it appears the previous owner was running this with 2 out of the 3 bolts in place, the 3rd broke off or something, and I need to remove it as well.



Any pro suggestions on broken bolt removal? I do have access to a standard drill/mechanics basic tools. I can also borrow an impact wrench and air compressor from my Dad.

Last but not least. After changing the rear end gear lube, it appears that I have some sort of leak. I am not sure where it is coming from exactly. At first I thought it was maybe the drain plug, but drips are forming between the drive shaft joint and the plug area itself the gask tank looks to also be sprayed by the gear oil from the drive shaft spinning back there.. How hard is something like that to fix? I might try to tackle it myself however I'd like advice from someone who's done it before, and what exactly its coming from in the first place, Pinion seal?



Thanks guys for taking the time to read and offer advice for this newb.

 

[Ahlem]

If any of the broken bolt is exposed, you can grab it with a small vice grips and turn it out. I'd use PB Blaster on it first.
If you can drill it down the middle without hitting the distributor casting, I'd pin punch the bolt remnants and get a left hand drill bit from an industrial supply house. You may be fortunate and have the bolt back out while you are drilling. This is a bit of an art that tool and die guys talk about.

 

[voiddweller]

If any of the broken bolt is exposed, you can grab it with a small vice grips and turn it out. I'd use PB Blaster on it first.
If you can drill it down the middle without hitting the distributor casting, I'd pin punch the bolt remnants and get a left hand drill bit from an industrial supply house. You may be fortunate and have the bolt back out while you are drilling. This is a bit of an art that tool and die guys talk about.

I tried that with pb blaster and vice grips , ended up breaking it off at the base, flush with the distributor base. Guess I need to buy an easy out set it looks like.