UPDATE: It turns out my hesitation issue was NOT due to the Throttle Body. I experienced the hesitation issue WITHOUT an engine light. When this happens you have to go to the dealership and have the TCM codes read. If you throw a code in the TCM then you'll have to get the CVT worked on.
This thread will apply if/when you experience the hesitation issue and get a check engine light with a code referencing throttle position or something similar.
Updated as per request from Warhammer. - njjoe
This thread describes how to replace the Throttle Body (TB), Spark Plugs, and the firewall Valve Cover. Refer to pictures throughout the writeup.
My MO is a:
2004 SL AWD
90K miles
K&N Panel Filter
Low PSI AC Line Insulation Upgrade
FAILURE MODE: MO sitting at a red light, engine warmed up and driving for ~30 minutes. Light turns green, push on gas pedal, RPM stay at idle. Completely floor gas pedal, MO slowly creeps forward then races off.
PROJECT TIME: 6-7 hours.
NOTE: This does not address the failure mode that others have seen where you push on the gas pedal, RPM's go up, and the MO does not move. This failure mode typically means the CVT is going bad.
About 2 weeks ago, I experienced the Failure Mode a couple times. Since then, I read a lot of threads about the issue. Every instance referenced having to replace the Throttle Position Sensors (TPS). There are 2 TPS's inside the black housing attached to the TB. Unfortunately, everything comes as a unit so you have to swap out the entire TB to resolve the issue.
I figured at the same time I would do a bit extra work and replace the spark plugs. I've heard that you can keep these plugs in the MO until after 100K miles. I say phooey because no spark plug on the planet will withstand 100K of driving. They start to loose their seals, spark density goes down, etc. I prefer to replace them in shorter intervals.
Of course, while working on replacing the TB and Spark Plugs, I ran into another issue! The drivers side spark plug tube had some oil in it!
The pictures later will describe how this happened but it did not make me a happy camper. :banghead: After doing some research on this forum as well; another reason why I love this forum, I found out that a few members had misfiring caused by swamped plugs. The oil level would eventually reach the top of the plug and the energy would short to the tube. Replacing the valve cover solved this issue.
So...here's my parts list and where I got the parts:
Nissan Re-manufactured Throttle Body (Reliable Nissan)
Throttle Body Gasket (AutoZone)
6qty Iridium Spark Plugs (PulStar)
Firewall Side Valve Cover (Reliable Nissan)
Firewall Side Valve Cover Gasket (Reliable Nissan)
I have a hook-up at Reliable Nissan hence the reason I bought the parts there. He can match and sometimes beat WorldPartsExpress pricing before shipping! :29:
The ultimate goal is to get the upper intake plenum off so we can get under it to replace the plugs and the valve cover.
The first picture (1.jpg) is your baseline. The instructions for the intake plenum and throttle body (1a.jpg) are found in the Service Manual.
Start by removing the air box, hoses, and engine resonator attached to the throttle body (2.jpg).
You'll see the TB exposed with all connectors that surround it (3.jpg). You'll have to remove the hoses and connectors that will interfere with removing the upper intake plenum.
Remove some of the other parts that are holding down the upper intake plenum (4.jpg). You'll have 2 more bolts and a couple more small hoses on the front face to remove.
You have some other hoses and bolts that need to be removed behind the upper intake plenum so you'll have to start removing the wiper arms, the cross member, and other stuff to get to them.
Start by marking where your wipers sit with some blue painters tape, remove the wiper arm caps to expose the wiper arm retaining nuts, remove the wiper arm retaining nuts, remove the wiper arms, carefully pop off the rubber hood seal, and remove the 2 round clips on each side of the plastic finisher (5.jpg).
While removing the plastic finisher, disconnect the windshield washer fluid tubing adapter as shown (6.jpg).
Remove the 3 the wiper motor bolts and disconnect the wiper motor harness (7.jpg).
Remove the 10 bolts that hold down the metal cross member (8.jpg).
Now it's time to start removing the things that are holding down the back end of the upper intake plenum. On the passenger side there are 2 hoses and 2 bolts (9.jpg). The arrows show where the 2 bolts are. The arrow on the lower left points to a connector...this connector is attached to a bracket that has the bolt.
This thread will apply if/when you experience the hesitation issue and get a check engine light with a code referencing throttle position or something similar.
Updated as per request from Warhammer. - njjoe
This thread describes how to replace the Throttle Body (TB), Spark Plugs, and the firewall Valve Cover. Refer to pictures throughout the writeup.
My MO is a:
2004 SL AWD
90K miles
K&N Panel Filter
Low PSI AC Line Insulation Upgrade
FAILURE MODE: MO sitting at a red light, engine warmed up and driving for ~30 minutes. Light turns green, push on gas pedal, RPM stay at idle. Completely floor gas pedal, MO slowly creeps forward then races off.
PROJECT TIME: 6-7 hours.
NOTE: This does not address the failure mode that others have seen where you push on the gas pedal, RPM's go up, and the MO does not move. This failure mode typically means the CVT is going bad.
About 2 weeks ago, I experienced the Failure Mode a couple times. Since then, I read a lot of threads about the issue. Every instance referenced having to replace the Throttle Position Sensors (TPS). There are 2 TPS's inside the black housing attached to the TB. Unfortunately, everything comes as a unit so you have to swap out the entire TB to resolve the issue.
I figured at the same time I would do a bit extra work and replace the spark plugs. I've heard that you can keep these plugs in the MO until after 100K miles. I say phooey because no spark plug on the planet will withstand 100K of driving. They start to loose their seals, spark density goes down, etc. I prefer to replace them in shorter intervals.
Of course, while working on replacing the TB and Spark Plugs, I ran into another issue! The drivers side spark plug tube had some oil in it!
The pictures later will describe how this happened but it did not make me a happy camper. :banghead: After doing some research on this forum as well; another reason why I love this forum, I found out that a few members had misfiring caused by swamped plugs. The oil level would eventually reach the top of the plug and the energy would short to the tube. Replacing the valve cover solved this issue.So...here's my parts list and where I got the parts:
Nissan Re-manufactured Throttle Body (Reliable Nissan)
Throttle Body Gasket (AutoZone)
6qty Iridium Spark Plugs (PulStar)
Firewall Side Valve Cover (Reliable Nissan)
Firewall Side Valve Cover Gasket (Reliable Nissan)
I have a hook-up at Reliable Nissan hence the reason I bought the parts there. He can match and sometimes beat WorldPartsExpress pricing before shipping! :29:
The ultimate goal is to get the upper intake plenum off so we can get under it to replace the plugs and the valve cover.
The first picture (1.jpg) is your baseline. The instructions for the intake plenum and throttle body (1a.jpg) are found in the Service Manual.
Start by removing the air box, hoses, and engine resonator attached to the throttle body (2.jpg).
You'll see the TB exposed with all connectors that surround it (3.jpg). You'll have to remove the hoses and connectors that will interfere with removing the upper intake plenum.
Remove some of the other parts that are holding down the upper intake plenum (4.jpg). You'll have 2 more bolts and a couple more small hoses on the front face to remove.
You have some other hoses and bolts that need to be removed behind the upper intake plenum so you'll have to start removing the wiper arms, the cross member, and other stuff to get to them.
Start by marking where your wipers sit with some blue painters tape, remove the wiper arm caps to expose the wiper arm retaining nuts, remove the wiper arm retaining nuts, remove the wiper arms, carefully pop off the rubber hood seal, and remove the 2 round clips on each side of the plastic finisher (5.jpg).
While removing the plastic finisher, disconnect the windshield washer fluid tubing adapter as shown (6.jpg).
Remove the 3 the wiper motor bolts and disconnect the wiper motor harness (7.jpg).
Remove the 10 bolts that hold down the metal cross member (8.jpg).
Now it's time to start removing the things that are holding down the back end of the upper intake plenum. On the passenger side there are 2 hoses and 2 bolts (9.jpg). The arrows show where the 2 bolts are. The arrow on the lower left points to a connector...this connector is attached to a bracket that has the bolt.
