KyleT

I have a 96 limited with 142k on it.
It has recently began to have a bad hessitaion/stutter starting at 2k rpm and continuing to about 3300 or so. it occurs under acceleration or load on the highway, but under light pedal effort. If i floor it, it will downshift and rev higher and it goes away, i first thought it was the trans, but i held in gear and it did it in 2, d, and Od.
where can I start to daignose this problem?
sometimes it wont downshift and i am stuck at about 60mph when going slightly uphill ect. with the pedal floored.

Thanks, Im relatively new to toyotas.

dirtypuke

i would start at the easy stuff first like maybe a fuel filter. i am sure if you do a search you will find alot of threads on this matter.

ebelen1

I can't help w/ the first part of your query but about not downshifting at 60 during inclines, I may be able to help. I have a '99 auto tranny and when I'm on the freeway on an incline, it doesn't matter how hard I punch the gas, the truck just revs higher, may or may not downshift, but pretty much stays put. I noticed that if I take the tranny out of OD, the sucker downshifts and pulls. I think the biggest cause of this is the much bigger tires than stock w/o regearing. Hope this helps.

KyleT

yeah, after the holiday im doing a "tune up" new plugs, fuel filter, air filter (it is not dirty though) dif fluid and transfercase fluids, as well as changing the oil. I did a seafoam treatment and it did not affect it. if that doesnt cure it, i guess ill replace the plug wires and then see what happens.
is there anyhting else i need to check?

MTL_4runner

Best bet is on the plugs or fuel filter (be sure to clean the throttle body when you do the plugs, idle will smooth out alot). If you still have trouble you might also want to check the TPS and clean the MAF.

This is a great link for basic maintenance (there are 5 pages total):
http://www.4x4wire.com/toyota/mainte...tenancep2.html

blown4runner96

I just had the same problem you are experiencing right now, or so its seems. I had a hesitation and stutter on full throttle. It started only on long road trips and at 75+ mph, but then increasing got worse and happened more often. I finally couldn't barely drive it. I pulled my s/c because the bearings in the snout were coming loose, re-installed the stock plenum and sent the snout out for repairs. The problem was still there, although my truck wouldn't pop a code (drove me ˟˟˟˟ing crazy) it was still missing on 4 of the 6 cyls. Anyhow finally got a code and replaced the cyl 5 coilpack in addition to the scored spark plug.

This may or may not be the problem, but check your coilpacks (indirect ignition), make sure you have no fuel managment problems and check your MAF. Although if these things get bad enough they should pop a code. I was lucky and have access to a scan tool to check my misfire percentages, fuel trim, etc....

KyleT

hmm, well, it feels like a misfire and does it when it is warm. ill check the coilpacks.
they used to go out often on the mazda miatas i was around when i was into racing.

i am 100% stock. only thing i added was xenons and took the runningboards off.
i have access to an obd2 scanner at work, would that be enough to pull those figures?

KyleT

oh, whats the ngk part number for plugs? and what is a good fuel filter recommendation? i tend to stay away from fram (just a personal preferance)

blown4runner96

In the beginning mine only missed after the engine got hot, hence long road trips. But as the coilpack worsened it became an all the time deal. Since I doubt you have access to a scan tool for your DLC3, try pulling the plugs to see if there is any scoring or other damage. Other than that, since you have no code it is hard to try and diag without knowing what component you're looking for. And it doesn't matter neccessarily what mods ya got going on.

I'll check with parts tomorrow about part numbers. And fuel filter really don't need replacement unless verified that they are bad, most fuel filters don't go bad within a resonable amount of mileage. I'd stay away from Fram too... they make chit products

MTL_4runner

OEM plugs (Densos or NGKs), OEM fuel filter (with 142k, I'd change it).

Change the plugs first and then see if that helps...then go into checking the other stuff (coil packs, TPS, etc).
Worn or bad plugs can cause all kind of symptoms (incl missing).

blown4runner96

In my diag of my stuttering issue on my 4Runner, I traced the scored plug to a coilpack... yes bad plugs and wires can definitally cause hesitation, although it is seem more with distrubtor run vehs. Your right if the plugs are orginal at 142K miles they've definitally been over worked. One way to tell is original plugs from the factory are different on each bank. I don't know why, but the spark plugs installes in the right bank are different than the ones installed on the left. But if one plug is extremely scored as mine was there is usally another related reason. Put my two cents in because I was having the same symptoms no more than a week ago and managed to fix it.

KyleT

i know it had the headgasket recall done early in its life, and was a one owner car, a guy bought it for himself, and then gave it to his son, who in turn traded it in on a new 2006 BMW 330i. and it has records of most of the stuff done to it, brakes, ect. even has the original window sticker.
Ill check back in the morning, and hopefully get someone to use the scan tool on my car at work tomorrow (i cant, i work in the front end, not in service)

blown4runner96

They may not be able to pick anything up at this point in your problem. And if it is in fact after the motor has gotten warmed up wait till you have the veh in condition for duplication. I was picking single digit misfire readings off the scan tool only after my conditioned worsened a little. Let me know what they find though and have them check fuel trim also if possible. These are all quick checks on data list in the scan tool.

KyleT

ok did the fuel filter, and air filter as well as an oil change.
i picked up the plugs,are there any suggestions to the best way to go about changing them out? i coukd barely get the wires undone on the drivers side, and i didnt even look at the passenger side.

MTL_4runner

This link should help with changing the plugs:
http://www.4x4wire.com/toyota/mainte...ep3.html#plugs

blown4runner96

indirect ignition... coil packs on right bank of motor (psgr side), held in by 10mm bolt. Don't pull on the wires themselves on the left bank or they will break... good link for the changing out spark plugs, especially with coilpacks. As for the plugs on the left bank, we always remove the ground bolt on the plenum and also move the hose that is held up by the plenum brace and then just go at it... if you bought Toyota plugs they are already pre-gapped, just double check them in case they've been dropped or manhandled in their hist.

MTL_4runner

Ditto on double checking the plugs because the few times I have seen people have problems right after, 99% of the time, this is the reason.

kawicowboy

I just went through everything you went through, the chugging, not wanting to downshift etc. Changed plugs and wires and just like that it was all gone, truck runs like a champ now.
Good luck.

KyleT

ok, im hoping i can get this worked out it is getting worse. i got NGK plugs, i dont know what the factory uses. i have had good luck with teh ngk's in the past.

KyleT

ok got the plugs in, pulled out some really bad looking splitfire ones. dont know why anyone would ever run those. they are not good.
put in the ngk's let it warm up and tested it out. no more hesitation, and it feels a little faster now too.
thanks for all the help.
now its on to mod it;