Engine Stutters on Hills

[foyaboya]

Hey all,
So I've been reading threads for days and have not found someone with the same issue.
My issue is not the same as T4RFool and others have experienced where the engine stutters at 4k rpm's: Backfire/Studder under acceleration ( 1 2 3 4 5)

My engine stutters when at highway speeds above 60 mph rpm's between 1500 and 2500 but it's only in the higher gears also like 4th and 5th:shrug: at those same rpm's in the lower gears I get no engine stutter. The kicker is I read in one of the threads someone asked the OP if it went away when the O/D button was off and as a matter of fact the stutter goes away when I turn O/D off. I think it's cuz it revs it up to 3 or 4k rpm's when you're going 70+mph and turn off O/D. The only other time is when it's in park when revving it but only when i first hit the pedal. I have a limiter on my other vehicle and know what that feels like at 4000 rpm and this is not the same thing.

No Check Engine Light or CEL for you acronym guys
(I did get a CEL this morning when I decided to gas it up to 85 or 90 mph but it went away a few seconds later)
Automatic Trans
275,000 miles
Timing Belt done @ 220k
oil level and pressure good
Engine temp good
Spark plugs good (maybe need to check the gap?)

Don't mind checking Fuel Injectors (Just don't want to if I don't have to) begin debate...

Don't mind checking coils, wires etc...just need someone to point me in the right direction.

I'm going to troubleshoot this weekend I ain't skurred to turn a wrench but want to get some good direction first so I don't waste my precious non existent time (just had my third kid a boy).
Any helpful (knowledgable:nerd advice fully appreciated

 

[Gerdo]

Would you say this happens during high load situations?

I'm thinking it's a fuel issue. I would start by replacing the fuel filter.

 

[foyaboya]

Would you say this happens during high load situations?

I'm thinking it's a fuel issue. I would start by replacing the fuel filter.

Gerdo,
You and this Forum give me hope for humanity! Thanks for the quick response...
I would say yes and no...yes on hills as the weight of the vehicle and downward force come into play but I live in Texas not Colorado we're talking like overpasses...LOL but kinda yes.

No because it does the stutter mildly when I rev it in park, but then again I am putting a "Load" on the engine when mashing the pedal...I purchased the fuel filter two nights ago just have not put it on...

Does the O/D on vs off ring any bells? The stutter going away at high RPM's? Thanks,

 

[ABOZEYAD]

same exact thing happened with my Mitsubishi 3000GT and the dealer told me it was the MAF sensor try this one it is dirty or faulty.. good luck

 

[FancyPantsMcGee]

By "stutters" you mean, loses power/misfires/hesitates/shakes?
If it is hesitating when you blip the throttle from idle;
Check vacuum. I'm at 5500ft and have 16 in/hg at idle.
FWIW; your transmission is a 3-speed with a 4th-gear overdrive. If you take it out of O/D your in 3rd. You can drive around in 1st, 2nd, and 3rd manually to verify if the condition is in fact gear related.
(sometimes I drive around in 2nd gear all day because it rules!)

 

[foyaboya]

same exact thing happened with my Mitsubishi 3000GT and the dealer told me it was the MAF sensor try this one it is dirty or faulty.. good luck

Cool did not think of that one. I'll definitely check it out and update with results. Now gotta figure out how to take it off and check it...more forum and Haynes manual searching...

By "stutters" you mean, loses power/misfires/hesitates/shakes?
If it is hesitating when you blip the throttle from idle;
Check vacuum. I'm at 5500ft and have 16 in/hg at idle.
FWIW; your transmission is a 3-speed with a 4th-gear overdrive. If you take it out of O/D your in 3rd. You can drive around in 1st, 2nd, and 3rd manually to verify if the condition is in fact gear related.
(sometimes I drive around in 2nd gear all day because it rules!)

on inclines: looses power yes
misfires no? it does not backfire if that's what you mean it could be a cylinder misfire but I'm not getting a CEL so no codes to be conclusive it it is misfiring??
hesitates: no
shakes: you mean besides the old suspension? LOL yes it shakes pretty bad when I experience the studders i mean..i mean..stutters.

Not to sound daft but how do i drive an automatic in 1st, 2nd, or 3rd manually? Drop it in L or L2? I'm asking seriously cuz i'd like to rule out transmission if i can!:wow:

 

[Gerdo]

Are the spark plugs the proper ones?
This engine only likes dual electrode NGK or Denso plugs. Others will cause poor performance.

 

[foyaboya]

Are the spark plugs the proper ones?
This engine only likes dual electrode NGK or Denso plugs. Others will cause poor performance.

I read that in T4rFool's thread...I know their NGK's the dual electrode part of my memory is failing me I'll have to pull them after work and check.

 

[FancyPantsMcGee]

I think you've got it. pull the lever down to L from park; that's 1st gear. It will stay in first no matter what so don't over-rev it! You just push the lever forward to 2 when you want to change gear. If you depress the O/D button to begin with; when you push it into D(3rd) it will stay in 3rd until you press the overdrive or pull it back to 2nd etc.
Going into and out of 1st gear while your driving can be a bit jarring so don't get crazy with it.
With the engine physically shaking I would lean toward an actual misfire. It may not throw codes until it misfires continuously.
I recommend a compression test. It's an easy one and narrows the possibilities.
If you have good compression, I'd look at the stock catalytic converter. A clogged cat will definitely cause power loss up a hill.

 

[Gerdo]

I had a non-fire from a bad plug wire but that was pretty constant.

 

[foyaboya]

I think you've got it. pull the lever down to L from park; that's 1st gear. It will stay in first no matter what so don't over-rev it! You just push the lever forward to 2 when you want to change gear. If you depress the O/D button to begin with; when you push it into D(3rd) it will stay in 3rd until you press the overdrive or pull it back to 2nd etc.
Going into and out of 1st gear while your driving can be a bit jarring so don't get crazy with it.
With the engine physically shaking I would lean toward an actual misfire. It may not throw codes until it misfires continuously.
I recommend a compression test. It's an easy one and narrows the possibilities.
If you have good compression, I'd look at the stock catalytic converter. A clogged cat will definitely cause power loss up a hill.

Compression test is a definite! How does one go about conducting one? Yea I was not wanting to hear "catalytic"...I've had plenty of CAT bad news with my 01' Taurus suckers got 4 of them. I do not have the tools to cut and re-weld a new Catalytic Converter so I hope it's not. We shall see Sat. morning.

 

[FancyPantsMcGee]

I recommend following the instructions from a haynes or chilton manual
I think you can download a pdf from this forum. ..guys?

a basic rundown:
pull the coil packs and spark plugs out. The point is to simulate a running engine, so you do not allow combustion to occur.
screw the compression gauge into a plug socket.
crank the engine a few times until the gauge psi stops rising. 5 or so cranks.
make a note, release the pressure.
proceed for all cylinders.
If something out of the ordinary happens like the psi draining off rapidly or one cylinder being 40 psi less than the others... bingo. The manual will have explanations for different gauge responses.
Good luck man! let us know what you find.

 

[foyaboya]

Prob not the MAF may need to Ohm test it...

additional info...
I did attempt the seafoam treatment...nothing...

During my lunch I went out and removed the MAF Sensor. Looks good to me except for the temp wire which should not be causing the stutter right?
Disclaimer-iphone pictures
Looking down into sensor

Temp Wire?


I'll take it off Saturday to do the ohm test and still clean it to make sure...might as well do the TB while I'm at it...

 

[foyaboya]

Partially solved!

Driving home the other day I finally got a CEL (check engine light) and Engine Code scanner at O'reiley came up with P0300, P0301, P0302, and P0306. first was random misfire and the rest were cylinder misfire banks 1 2 and 6. In trying not to spend to much money all at once I bought new (aftermarket) wires and NKG plugs. I installed the wires right there in the parking lot and noticed a vast imporvment. Engine no longer stutters, at all! yay however it has less power than before?? I can gun it and the vehicle accelerates slower than before and my top speed is no where near before. I can only get it up to about 78 or 80 where as before I could easily hit 90+ even with the stuttering? So I'll replace the plugs next then maybe the insulators as DeTwizzle suggests?? http://www.toyota-4runner.org/3rd-gen-t4rs/123067-al-tapping-engine-bay-arching-sparking-plug.html
Anyone else have any other suggestions? I have no more stuttering but a loss of power with no check engine light?

 

[foyaboya]

scary moment

oh and when removing the boot from cylinder 4 on passenger side I had a heck of a time pulling it out (chuckle) and when I went to put the new boot in it only went in halfway...my next words were oh *&%^. I looked in with a light and the interior metal sheathing/jacket was stuck to the spark plug! Luckily it took me about 20 min and much of praying to get it out with a pair of needle nose pliers! Whew! Make sure and put plenty of that Spark Plug Boot Protector lubricant!

 

[FancyPantsMcGee]

The random misfire plus other misfires leads me to ignition coils(coil packs).
You can do a resistance check on them.
With a change in drivability immediately following a plug wire change I think your on the right track.
Also: I cannot recall a part on the 5VZ that meets the description given by detwizzle.

 

[colio]

I am having a very similar problem, (Stuttering in high gear under load) and I'm curious if you ever found a satisfactory solution. I am going to try the following to try and solve the problem,

start by replacing the fuel filter
I've done this before 2 or 3 yrs ago? and can do it again fairly easily

Check the MAF sensor

Change the spark plugs and cables

Check the coil Packs,


If anyone has any advice please let me know.

 

[kball]

I am having a very similar problem, (Stuttering in high gear under load) and I'm curious if you ever found a satisfactory solution. I am going to try the following to try and solve the problem,

start by replacing the fuel filter
I've done this before 2 or 3 yrs ago? and can do it again fairly easily

Check the MAF sensor

Change the spark plugs and cables

Check the coil Packs,


If anyone has any advice please let me know.

If it stutters in high gear/overdrive while at highway speeds but stops if you down shift, I'd start with the spark plugs.

 

[foyaboya]

I am having a very similar problem, (Stuttering in high gear under load) and I'm curious if you ever found a satisfactory solution. I am going to try the following to try and solve the problem,

start by replacing the fuel filter
I've done this before 2 or 3 yrs ago? and can do it again fairly easily

Check the MAF sensor

Change the spark plugs and cables

Check the coil Packs,


If anyone has any advice please let me know.

The ultimate fix for me was replacing the spark plugs (make sure their NKG) and wires. Based on my code i took a gamble and only replaced one of the coil packs (you should have three like mine) only because their 65 bucks a piece. If you have the cash replace them all if the wires and plugs don't resolve the issue. You can test the coil packs as well, but like i said I got lucky and the first coil pack i replaced resolved the issue. I did not replace MAF sensor. Good Luck! Asking questions on this forum will get you plenty of help!<?xml:namespace prefix = o ns = "urn:schemas-microsoft-comfficeffice" /><o></o>

 

[Whuskey]

Chugging going uphill

So I started a road trip to Tennessee from New Mexico with a friend. About 18 hours by google maps. 4Runner started misfiring like all get out about 30 miles in. I looked on YouTube and forums to see what could be the problem. Felt like going uphill with slight throttle was too much for failing fuel pump. Thought it could be clogged fuel filter or dirty injector. Replaced fuel filter in parking lot of hotel 2nd night in. No success. Coil packs could cost $150 from auto zone and didn’t want to shotgun those without trying some other things. Tried plugs and wires on 3rd night and BAM discovered #6 plug boot pulled right off and left metal part on spark plug. Needle nose pliers got that part off and I continued to replace plugs and wires. She runs like a dream now. NOTE. The coil packs are stock OEM... as were the wires and plugs. 220K miles. I replaced the plugs and wires in a parking lot with a couple tools from Harbor Freight. Easiest job ever. Check those first! My car never threw a CEL but it chugged so hard I thought the cars in back of me could see it... $78 from autozone for some new NGK plugs and a Duralast wire set. Some of you guys might still have stock OEM parts that are starting to fail! Check with cheapest/easiest parts first before thinking it’s something more expensive. These engines are amazing.