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Discussion Starter #1
i know this has probably been discussed before, but i searched and i couldnt find the answer. Anyways, i went to a mechanic to get my timing advanced and he said that it would be a waste of time to get my timing advanced on my car, because the ecu would just retard it back to where it should be. Is this true or is he just stupid? btw i was reccomended to this mechanic by another mechanic specifically for timing advance.
 

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depends....if it is advanced too far, the knock sensor would warn the ecu which would knock it back to stock specs..but if its advanced to 15* then there would be no harm(as long as u run premium fuel)
 

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Discussion Starter #3
so as long as i run premium fuel and advance it to just 15*, the ecu wont retard it back to 10*. i told the guy that and he seemed pretty convinced.
 

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Discussion Starter #5
ok thanx, i was confused for a sec, ill just go to another mechanic, i dont want to do it myself im too lazy
 

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Please Shift Here
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You should take the 2 TPS sensors off to get into "timing mode." With the car running, pull the TPS plugs from the throtte body. It will not throw the CEL, you'll hear the tone of the engine change, then it'll adjust itself accordingly. Rev the engine 2-3 times past 2,000rpm, then adjust. Make sure you don't have any accessories on and the fans are not on when you check the timing light.

If you can borrow a timing light, just do it yourself, it takes about 10 minutes, all you need is a 12" socket and a flat head. It's not worth paying someone to do it.
 

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Ninety-Nine SE-L said:
You should take the 2 TPS sensors off to get into "timing mode." With the car running, pull the TPS plugs from the throtte body. It will not throw the CEL, you'll hear the tone of the engine change, then it'll adjust itself accordingly. Rev the engine 2-3 times past 2,000rpm, then adjust. Make sure you don't have any accessories on and the fans are not on when you check the timing light.

If you can borrow a timing light, just do it yourself, it takes about 10 minutes, all you need is a 12" socket and a flat head. It's not worth paying someone to do it.

there is only one TPS. You have to unplug the TPS while the car is OFF, then turn the car on.
 

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Notes:
- Sometimes the engine will not idle in timing mode. If this happens, start the engine and hold the accelerator to keep the engine running at idle speed while adjusting the idle speed screw.
- Advancing the timing makes the engine run faster, so the idle must be adjusted after changing the timing.

Here is the procedure from the B14 Factory Service Manual

Timing
1. Warm up the engine until the temperature gauge points to the middle
2. open the hood and run the engine at about 2000rpm for about 2 minutes under no-load.
3. Rev engine two or three times under no-load and then run at idle speed for about 1 minute.
4. Turn off the engine and disconnect the throttle position sensor harness connector.
5. Start engine.
6. Rev engine (2000-3000 rpm) 2 or 3 times under no-load, then run engine at idle speed.
7. Check ignition timing with a timing light.
7a. Adjust ignition timing to the desired value by turning the distributor after loosening bolts which secure the distributor.

Idle
1. Rev engine (2000-3000 rpm) 2 or 3 times under no-load, then run engine at idle speed.
2. Adjust idle speed by turning idle speed adjusting screw.
M/T 625 +/- 50 rpm
A/T 725 +/- 50 rpm (in "N" position)
3. Stop engine and connect throttle position sensor harness connector.
4. Start engine
5. Rev engine (2000-3000 rpm) 2 or 3 times under no-load, then run engine at idle speed.
6. Check idle speed.

Lew
 

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Well, sicksilver99, you have a choice. You can follow the factory recommended procedure or the one posted by Ninety-Nine SE-L. I am confident that the factory recommends turning off the engine before disconnecting the sensor for a reason, but that's just me, a person who was working on cars before Ninety-Nine SE-L was born.


It seems to me that having two throttle positition sensors would require having two throttle bodies each with a throttle to sense. It's hard to believe the factory put duplicate sensors on the same throttle.

Lew
 

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lshadoff said:
Well, sicksilver99, you have a choice. You can follow the factory recommended procedure or the one posted by Ninety-Nine SE-L. I am confident that the factory recommends turning off the engine before disconnecting the sensor for a reason, but that's just me, a person who was working on cars before Ninety-Nine SE-L was born.


It seems to me that having two throttle positition sensors would require having two throttle bodies each with a throttle to sense. It's hard to believe the factory put duplicate sensors on the same throttle.

Lew
I don't believe its two sensors. I think its just one sensor with two plugs for some reason. Started in 97 vehicles.
 

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James said:
I don't believe its two sensors. I think its just one sensor with two plugs for some reason. Started in 97 vehicles.
My '97 FSM doesn't think so. It shows a single 3-wire connector for both the GA and SR engines.

Lew
 

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lshadoff said:
My '97 FSM doesn't think so. It shows a single 3-wire connector for both the GA and SR engines.

Lew
Honestly lew, James is correct. I have both throttle bodies and sensors to prove it. I am not 100% certain that both of them have to be disconnected but I GUARANTEE they connect at the throttle plate.
 

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There are only three wires to the TPS, one of them is shielded.

My SR has one 3-wire connector to the TPS and separate ones further down the cable for the shield ground and signal to the A/T computer.

The GA wiring diagram shows one 3-wire connector to the TPS and a separate one for the shield ground.

Disconnecting the 3-wire connector on either of them isolates the TPS.

Lew
 

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I never said there are 2 actual sensor units, jus 2 plugs. I believe there are 2 3-wire plugs on there. Here's what I got from a page:

"An SE-R mailing list member told me that only the the 1998 and 99 models come with two plugs. I f you have a pre-1998 model you should only have one plug. That will be your TPS."

So whatever, just unplug however many plugs are going to your throttle body and do your business. If you want to turn off the car to unplug the TPS, then fine. I do it with the car running, no difference whatsoever in my experience, both of my cars. It's not rocket science, if you want to talk about rocket science, you can PM me.
 

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Ninety-Nine SE-L said:
I never said there are 2 actual sensor units, jus 2 plugs. I believe there are 2 3-wire plugs on there. Here's what I got from a page:

"An SE-R mailing list member told me that only the the 1998 and 99 models come with two plugs. I f you have a pre-1998 model you should only have one plug. That will be your TPS."

So whatever, just unplug however many plugs are going to your throttle body and do your business. If you want to turn off the car to unplug the TPS, then fine. I do it with the car running, no difference whatsoever in my experience, both of my cars. It's not rocket science, if you want to talk about rocket science, you can PM me
Are you sure about the rocket science comment, Lew is one who just might PM you on that...
 
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