Alright, before I let my hair go gray any quicker than it should I'm going to consult with everyone here. When you turn the shark off and come back after maybe 30 to 40 minutes she doesn't like to start, I have to turn her over at least three times with my key until she finally starts up. Last year my shark was in the process of being restored with a bunch of items it needed. I purchased the 4 hole injectors for her from Roger, she had plenty of other problems at the time like needing a new MAF sensor so I figured when she wouldn't start right when hot was because of the mad sensor needing to be swapped. Finally got a brand new MAF sensor from Roger, still didn't like to start when hot. So I thought okay, the fuel regulator and fuel dampers were never changed, so I got the billet ones from Roger. Still nothing. Alright, fuel filter and fuel pump hadn't been done in a looooong time, so I ordered them from Roger and changed the check valve on the fuel pump. Still no hot start. Cold starts are just fine, no problems what so ever runs and drives great. Fuel pump relay was replaced with a new one just because I was swapping out all the old relays. I even swapped out the old LH relay with a new one. I have jumped the fuel pump to ensure it works too. I'm assuming it's vapor locking? I honestly don't know though. Any advice is greatly appreciated because I don't know where to go from here. I have looked up to see if anyone else has similar issues but I only saw issues from the earlier models and I know the fuel system is different than the S3. I don't see or smell any fuel leaks, I don't hear any bubbling anywhere. Where do I go from here?

 

Check that the temp2 sensor is working correctly.

 

put some techron and 6 oz of MMO in the gas do short drives,
put a fuel pressure gauge on the rail and monitor the fuel pressure,
Did you set the MAF up for proper mixture?
your year requires this to be done then reset the idle speed.

NOTE setting the MAF procedure will also let you test the computer idle circuit disable,
this will indicate if the computer drivers have been damaged by a bad ICV thats got a sticking vane.


https://rennlist.com/forums/928-foru...=adjusting+MAF

NOTE send the old injectors out for cleaning and swap them back in if none of the other things make the engine start easier.

 

Don't have the older injectors anymore, they didn't look too go so unfortunately they got tossed without a second thought. Definitely did not know there was a procedure for the MAF, I thought you just plug it in and it does its thing haha.

 

How did you go about disconnecting the o2 sensor? Did you just disconnect it at the exhaust or is there a plug I can disconnect at the panel?
Wish there was a video of someone doing the MAF adjustment haha.
Edit: just read that there is a harness near the fuse panel, I'll have to take it apart this weekend and do this whole procedure. Hopefully I don't have any additional problems driving it the few times to work the next two days.

 

why are you disconnecting the O2 sensor? to change it?

There is a connection point at the CE panel for the O 2 sensor
then the wires / rubber grommet are passed out through the chassis hump,
use a screw driver to push the rubber grommet out.

 

I was reading your write up about the MAF adjustment and it said to disconnect the o2 sensor, so I was making sure I understood what you meant by disconnecting it. I did end up finding the main wire for it that comes up through the rubber grommet, just need to get to the connector behind the fuse panel as it seems to be stuck behind it.

 

If you have a hot start problem on an S3, you can try depressing the accelerator while starting. This seems counter intuitive to a fuel injected car, but when my S3 was misbehaving, it would start up if I treated it more like a carb car.

A couple things to check - do you have oil in one of the plug wells?
Are you organ pipe rubber connectors all proper?

Both of those can cause start up problems in the S3

 

I've done the pressing the accelerator down when starting and it sometimes works, sometimes doesn't. In regards to plug wells, I would hope not since I did a car cover reseal recently since I had some oil in it before from a split seal. I'll check again though this weekend. By organ pipe connectors, what is this referring to? The vacuum lines?
Edit: I think you mean the rubber for the intake on top right? Yeah those are all brand new rubber with brand new clamps, so those are definitely all good.
Edit 2: I also noticed that the exhaust smells a bit rich, and since I havent done what mrmerlin stated about adjusting the MAF afr, I have a feeling that probably has something to do with the situation as well.

 

I think the pressing accelerator is a coping mechanism, rather than fixing whatever is causing the hot stop problem.

Yes, 'organ pipes' refers to the S3 intake (only model year 85/86 had them). The rubber booties can be loose, or be pinched underneath, and when they are improper they let in unmetered air that causes all kinds of annoyances. There's alsothe rubber connector between the MAF and the throttle body, plus the one at the bottom of the big center T.

I think of the spark plug well seals as "fish lip" seals, bc that's what they looked like on the Alfas I used to work on. The damn fish lips are tricky - I'm about to reseal mine with Drei Bond.

 

Yeah I recently replaced the rubber for the intake when I powder coated the intake pieces along with the clamps, and I got those on nice and good so I don't think that has anything to do with my situation. And I don't think the rubber on the center T is bad when I took it apart the rubber looked good still.
When I did the cam covers I used a good amount of Honda bond on every single rubber piece I saw, but I'm gonna check again this weekend to see if I see anything, hopefully I don't see any oil or I might have bigger problems than a rubber seal.

 

NOTE if the exhaust smells rich after installing a new MAF,
thats your indication the mixture has to be set prior to resetting the engine idle speed,
now you understand that your nose can be a guide to finding a good mixture.

NOTE the 85/ 86 MAF injection systems did not have the mixture regulation that the S4 series cars have .