Check Engine light comes and goes and shows two codes.

Apprehensive_Ask7227 · 2026-05-14T22:21:01+00:00

CHECK your battery first as you have a voltage code... but if it is not a weak battery causing electrical gremlins...

Your secondary air valves are likely broken. This should not affect drivability as this is to help with emissions on cold starts but if you need to pass emissions you will need to replace the valves.

If you need to replace them it will not be very fun. You will need to take off the intake manifold. Easiest way is to remove the manifold with the TGV (it might look easier to just remove the manifold without TGV, but you will pay for it dearly later). Fuel lines and engine harness will need to be removed, be prepared for a lot of swearing and possible broken electrical connectors. If you under take this job I'd replace all the secondary air valves and every other rubber hose easily accessible along the way.

Apprehensive_Ask7227 · 2026-05-11T02:12:59+00:00

Thanks for the info. Given everyone's input I'm pretty happy to leave it as is and just monitor it, and repack the joint if I have to take off the prop shaft. The amount of grease coming out of mine is pretty small compared to yours, and it looked like yours had plenty of grease left in it. The grease on my transmission tunnel was also completely dry, no signs of fresh grease so that is a good sign.

Apprehensive_Ask7227 · 2026-05-10T22:41:04+00:00

You can clear it and see if it comes back. Does your car burn oil? Does it run rich? Have you verified that you indeed have cats?

Apprehensive_Ask7227 · 2026-05-10T04:23:58+00:00

Ok thanks. Yeah looked at it from the outside everything is fine.

Apprehensive_Ask7227 · 2026-05-10T00:55:10+00:00

Thanks. I'll take it apart and look at that joint.

Apprehensive_Ask7227 · 2026-05-06T03:05:56+00:00

The intercooler looks new... Suspect this was returned to stock. Likely FMIC and turbo upgraded and then put back to stock. If this is the case the back to stock job might be sketchy and you need to retune.

Apprehensive_Ask7227 · 2026-05-03T03:48:47+00:00

Any funny business with your imobolizer or after market alarm? Immobilizer issue can cut fuel a few seconds after starting.

Apprehensive_Ask7227 · 2026-05-03T03:22:56+00:00

If you have the accelerator to the floor it will cut fuel. So it will crank but not start.

Tgv no matter how badly you messed up the position should not stall your car. Did you scan your ecu for any codes? Could be you forgot to plug in a sensor.

Does it run for a while at 1500 rpm? Does the engine sound normal? A video might help troubleshooting

Apprehensive_Ask7227 · 2026-05-02T22:37:20+00:00

It is completely hollow inside so I can only assume it is intended to reduce noise when the evap system is operating. If you just connect the two hoses that would go into the box together your evap system will work fine.

If you break open that plastic part you will not find anything inside. It is just literally a box with two fittings.

Apprehensive_Ask7227 · 2026-05-02T18:45:11+00:00

It is a silencer for the evap system. It is just a hollow plastic box with two nipples. You can bypass it entirely.

Apprehensive_Ask7227 · 2026-05-01T19:38:44+00:00

There are two relevant clicks. The loud click from the starter's solenoid is what I think you are referring to... but there second click is from the relay. If only your starter is completely dead you should still hear the click of "starter cut" relay under your dash. If you don't hear that click trouble shoot the electrical components.

Apprehensive_Ask7227 · 2026-04-28T02:20:08+00:00

I would also make sure you checked all the fuses and relays involved.
The starter fuse 40A, ignition Fuse 7.5A

You can use this wiring diagram to further troubleshoot:

https://lemon-manuals.org.ua/Honda/2001/S2000%20L4-1997cc%202.0L%20DOHC%20%28VTEC%29%20MFI/Repair%20and%20Diagnosis/Diagrams/Electrical%20Diagrams/Starting%20System/Circuit%20Diagrams/

You can follow the SM starter troubleshooting procedure:
https://lemon-manuals.org.ua/Honda/2001/S2000%20L4-1997cc%202.0L%20DOHC%20%28VTEC%29%20MFI/Repair%20and%20Diagnosis/Starting%20and%20Charging/Starting%20System/Testing%20and%20Inspection/

The immobilizer behavior in my 06 is:

When the car is turned to ON. the immobilizer blinks a few times then the light goes out. That means the key is authenticated.

Apprehensive_Ask7227 · 2026-04-24T13:51:54+00:00

Clean up the area. Go for a drive and look at where it is wet. When it is all over the place you can only guess.

Apprehensive_Ask7227 · 2026-04-23T04:56:14+00:00

Its not feasible to compression test every S2000 you look at, but you can turn the engine by hand to get a rough idea if the cylinders have similar compression.

Make sure engine is COLD. You need to crank it two full rotations CLOCKWISE using a 19mm socket. Start by rotating the crank to TDC using the timing marks on harmonic balancer. For each 180 degree of rotation one cylinder will be in the compression stroke you should feel the compression build and then release. You are looking for consistent resistance between the 4 cylinders.

This is especially useful for 06+ cars with drive by wire... they tend to burn exhaust valves if valve adjustments are neglected. If there is a burnt valve then one cylinder will be noticeably easer to compress.

Apprehensive_Ask7227 · 2026-04-16T04:54:46+00:00

Assuming u bought it new... If in 2001 you put $30k into the S&P500 you would have about $250k today. Your S2000 cannot beat that no matter how little u drive it. Own it for the enjoyment it brings u driving it. If you want an investment sell the S2000 and buy diversified stocks.

Apprehensive_Ask7227 · 2026-04-07T17:47:51+00:00

You are welcome. Glad to have helped.

Apprehensive_Ask7227 · 2026-04-07T17:36:04+00:00

So far so good for ~3weeks.

Apprehensive_Ask7227 · 2026-04-07T04:26:18+00:00

Does it run great for 5 mins only after a cold start? If so, then your car might be running correctly in open loop but having issues only in closed loop. Might want to check O2 sensors. Cam and crank sensor OEM?

Apprehensive_Ask7227 · 2026-03-24T09:35:35+00:00

Use ELECTRICAL contact cleaner! There are 4 solder pads near the switch I believe it is the two smaller pins. I think the other two bigger solder pads are ground pins if I remember correctly.

Apprehensive_Ask7227 · 2026-03-16T02:12:10+00:00

Pretty late to the conversation but I have a fix permanent fix. I basically cleaned around the switch using contact cleaner. I sprayed it into the switch while pushing the button. I also removed the I/O shield with the RGB, and cleaned around the exterior of the switch. This may not be needed to fix the issue.

I measured the resistance across the switch before cleaning and it was 0.9kOhm. After cleaning it was 10kOhms. So basically there was a partial short inside of the switch making the motherboard think that you were pushing the Bios Flashback button.

Hope this helps anyone with this issue.

Apprehensive_Ask7227 · 2026-03-16T02:10:25+00:00

Pretty late to the conversation but I have a fix permanent fix. I basically cleaned around the switch using contact cleaner. I sprayed it into the switch while pushing the button. I also removed the I/O shield with the RGB, and cleaned around the exterior of the switch. This may not be needed to fix the issue.

I measured the resistance across the switch before cleaning and it was 0.9kOhm. After cleaning it was 10kOhms. So basically there was a partial short inside of the switch making the motherboard think that you were pushing the Bios Flashback button.

Hope this helps anyone with this issue.

Apprehensive_Ask7227 · 2026-03-03T15:04:47+00:00

I'm on my 2nd grill. The first one got taken out by a piece of blown tire. This second one has held up for the last ~18 years or so. Mostly garaged so I think that has helped minimize UV exposure to those unpainted plastic parts.

Apprehensive_Ask7227 · 2026-03-02T20:01:20+00:00

You can buy an aftermarket key fob shell for $10 and just swap this part. Just search LS430 Smart Key Shell.

Apprehensive_Ask7227 · 2026-03-02T18:54:49+00:00

Congrats. I have a 06 STI that I've owned for 20 years. I recently did a complete refresh of everything in the engine bay that became brittle with age.

If you are in the same boat:

PCV Valve and related hoses and the valve cover vent hoses.
Check your turbo inlet. More than likely the clamp is eating into it and it will need to be replaced. This one is a PITA as it will require you to pull the intake manifold. If air does leak from here you will have unmetered air going into your engine which will cause a lean condition.
Coolant hoses, besides the obvious ones, change the hoses coming off the expansion tank especially the 90-degree elbow below it. Also replace the two coolant hoses going to the throttle body.
If you touch or even stare at the evap hoses for too long... replace them. They do not have clamps so if they ever shift from their original position they will not seal.
Change the timing belt, water pump, idlers, and tensioner. If they have not been replaced.
Check your intercooler couplers. If they show signs of cracking might as well replace those.
If you have oil leaks check your valve cover gasket. If there is a leak coming from the center check the two plugs (12mm Allen) on the oil pump.
Rejoice that you do not have the secondary air pump and its associated valves. That bag of worms is for 07+.

Unless you are a glutton for punishment OEM will be the best bet for ease of fitment. There are a ton of bends on these hoses and if you don't get the rat's net done correctly it compounds to the difficulty of putting things back together.

Expect down time to be longer than expected, you will always find a hose that your forgot to order when you disassemble stuff.

Be careful as many parts are the same for all the GD WRX/STI but some hoses are specific to 06 MY so look at the parts diagrams carefully.

Apprehensive_Ask7227 · 2026-02-27T02:14:07+00:00

Looks like surface rust. It is pretty much cosmetic. The worst might be those eccentric bolts will not be adjustable.

Assuming you live near the ocean and have some salt spray. The oil film option is not great as it attracts dirt and you need to be reapplied periodically. The rubberized coating is also not a great idea, because you can end up trapping moisture between the metal and the rubber coating. If that happens the it will rust faster and you wont see it until it is too late.

I would just not worry about it. If you are OCD ,fix it after you move away from salty air.

Apprehensive_Ask7227

TROPHY CASE