1993 Landcruiser acceleration hesitation

[TyWeed]

I have an intermittant hesitation on acceleration that goes away after the engine is warmed up. I am not getting a CEL or any associated diagnostic codes.

New injectors, fuel filter, plugs and wires, egr valve components (except the temperature gauge), distributor cap and rotor, starter. The timing is correct.

This happens every so often, but runs great after about 3 minutes of warming up.

Any thoughts out there? My first suspect is that egr temperature gauge that I did not change when I changed the egr valve and filter.

Any association with auto trans code 62 (or is that a whole different thread for me to start)

Thanks for any ideas (and yes I am a newbie)

 

[CruiseOrlando]

Mine exhibited similar behavior when the line from the charcoal canister to the VSV came off. I didn't notice it until the truck started behaving oddly - I imagine it was when the VSV opened up that it had issues.

Once the line was put back on, it took about 15 minutes for it to sort itself back out again, but eventually the issue went away.

So check and double-check all your lines, vacuum lines, etc - make sure you don't have any leaks or broken/missing hoses.

 

[TyWeed]

Hi Orlando, sorry for delay in response. Still learning how to use this website. All my lines are ok, I checked them religiously. And my charcoal canister is new. (found out how to replace that on the forums for 35 bucks.

Reason I am wondering about the EGR temp sensor is because when the engine warms up after a few minutes, the problem goes away.

Only codes i get are auto tranny code 62.

My only other thought is the throttle position sensor.

By the way, nice rig, mine is the same color. Any good public places to off road in south florida?

 

[CruiseOrlando]

Come over to the Florida clubhouse section to talk about offroading - we go out now and again!

FL- Florida Land Cruiser Association

It could be VSV related. I'm not 100% sure, but as the engine warms up, that valve is trying to do its thing.

Perhaps a cracked line? Taking some starting fluid and spraying around vacuum lines can help you detect leaks.

 

[TyWeed]

I will try the spray test and recheck the VSV valve. Thanks for the tips and will repost any revelations I make.

Gonna check out the florida link for off road adventures. My work colleague also has a cruiser and wants to get out there.

Later.

 

[jlg32281]

I have a similar issue and I've replaced the VSV. I also have a new intake hose, plugs, wires, distributor car and rotor. All OEM parts and I still have the hesitation from around 1800 rpm-2800 rpm.

 

[CruiseOrlando]

So... how's your gas mileage?

O2 sensors are another culprit of this behavior. From the '96 FSM:


HEATED OXYGEN SENSOR INSPECTION
INSPECT HEATER RESISTANCE OF HEATED OXYGEN SENSORS
(a) Disconnect the heated oxygen sensor connector.
(b) Using an ohmmeter, measure the resistance between terminals +B and HT (the top two prongs closest to the wire leading to the sensor)


Resistance: 11 − 16 Ω at 20°C (68°F)

If resistance is not as specified, replace the heated oxygen sensor.

(c) Reconnect the heated oxygen sensor connector.

 

[TyWeed]

I have a similar issue and I've replaced the VSV. I also have a new intake hose, plugs, wires, distributor car and rotor. All OEM parts and I still have the hesitation from around 1800 rpm-2800 rpm.

Have you checked EGR valve components. Changing those did wonders for my cruisers performance. Also, as Orlando recommended to me, the Vaccume Switch Valve (vsv) is temperature and rpm controlled. Perhaps an old hose/vaccume issue.

 

[TyWeed]

Come over to the Florida clubhouse section to talk about offroading - we go out now and again!

FL- Florida Land Cruiser Association

It could be VSV related. I'm not 100% sure, but as the engine warms up, that valve is trying to do its thing.

Perhaps a cracked line? Taking some starting fluid and spraying around vacuum lines can help you detect leaks.

Hey Orlando, how does one get access to the florida land cruiser association?

 

[CruiseOrlando]

Hey Orlando, how does one get access to the florida land cruiser association?

I thought everyone did?

Maybe you have to pass your probation period after you post 10 times or something? Not sure... if that link doesn't work for you, just get your post count up past 10 (I think?) and try again.

 

[TyWeed]

I thought everyone did?

Maybe you have to pass your probation period after you post 10 times or something? Not sure... if that link doesn't work for you, just get your post count up past 10 (I think?) and try again.

I was able to read some threads but probably have to pass the probation period of some sort.

Have you been to 3 lakes WMA in florida. Looks like a good place to get dirty.

Oh, my hesitation issue seems to happen when it is super humid. Or I am going crazy.

 

[CruiseOrlando]

3 Lakes WMA? No, I haven't, but I should have! I need to get over there - if you can drive in it. A lot of the WMA's you can't drive in.

The most frequented spot is Richloam by those of us that don't mind getting mud on our rigs. It gets kinda boring after you've gone to "real" wheeling places, but it's one of the only free decent places we have in Florida, and it's huge. They seem to make new trails (fire breaks really) from time to time and that keeps it interesting.

The other thing that keeps it interesting is getting stuck out there all alone...

As for the hesitation, I've never noticed humidity having an effect, but that doesn't mean it doesn't. Don't forget about the O2 sensor issue. I actually just ordered a new set for mine - partially due to rough idle, partially due to poor gas mileage.

 

[TyWeed]

Always enjoy seeing the pics of off road action. Just finished reading your build thread. Man, these trucks are addictive, eh? But fun and rewarding to do the job yourself.

By the way, what was the pcv hose oil water fiter for?

My 02 sensors were replaced with the cat converters 6 months ago. I just need to keep farting around with it to figure out my problem. It does not seem to be serious, just intermittant and annoying.

 

[TyWeed]

Just an update to finish the thread.

I checked the codes for the auto trans and after seeing code 62, replaced solenoid 1 and 2.

Also got rid of the PAIR system.

Truck runs great without hesitation, and noticable increase in power.

No codes!!!

Next project is to get rid of the EGR crap. Less parts, less hoses, less things to break or develope vacuume leaks.

 

[mypancreasbroke]

Just came across this thread. Sounds like the problem I am having. After swapping o2 sensors and disabling my EGR I immediately had hesitation problems. I attributed to an idiot mistake I made in overfilling the engine with oil (while changing the sensors I remembered my oil light had started coming on, so just dumped in what I assumed was about a 1qt... but eye balled it wrong from a big jug). After draining the engine oil to be right at the F my problem was much better, but still have a really annoying hesitation for the first 2-4 minutes of driving. I know nothing about transmission solenoids, so I wonder if that could also be my issue? I too haven't found a culprit hose, and have always assumed it was something related to my new o2 sensors... off work this week so I plan to nail it down and fix it for good.

 

[FJ80HI]

Just an update to finish the thread.

I checked the codes for the auto trans and after seeing code 62, replaced solenoid 1 and 2.

Also got rid of the PAIR system.

Truck runs great without hesitation, and noticable increase in power.

No codes!!!

Next project is to get rid of the EGR ****. Less parts, less hoses, less things to break or develope vacuume leaks.

What is PAIR system?
Regards