Alright, so I let the car warm up for a couple minutes then I take it for a boost or 2 around the block, when I get back and park it and turn it off, if I try to start it right away again, even within a couple seconds of turning it off, it wont start. After about 15-20 minutes it will start again but doesn't want to idle on its own for about 30 seconds and I have to make it idle. After that then its good to go again. What do you think might be the problem? What does the ECU change when a hot start condition exists?

 

how recent are the plugs? have they seen any abuse? (ATF, oil, severe cold flooding, etc)?

just an idea....

 

Ya I was thinking it might be the plugs, they are the same plugs that have been sitting in the car for 2 years, I cleaned them off a bit when I got the car, but then I did the ATF and they are pretty dirty and bad now. I'll try getting new ones and see if that helps.

I also just did a compression test, I let it build up to the max compression and I got about 90psi for the front and 80 for the rear.

 

its called lack of air, i had that problem with my stock airbox, i got the hks air intake and i never hard that problem, whats happening is it cant pull emough air to get started. Because the air is host the oxygen is completely gone from it

 

Hmm I guess I'll try drivin the car around gettin it warmed up and park it, make sure it wont start, then take the airbox apart and take the filter out and see if it will start. I don't see why the stock intake system would be the problem though, it worked fine on hot starts when the car came out.

I tried flooring the throttle while starting too, didn't help.

 

man you cant just go boosting all over the place and turn the car off as soons as you get in the driveway. The oil and coolant that is in the turbo will just sit in the hot *** turbo and cook itself. My black 88 TII does the same thing..if i run boost and then cut it off as soon as i get to where im going. then when i start it, it runs like crap for a few minutes until it gets over the 300 degree water and oil that was just sitting in it then it is fine. Either dont boost when u know u are going to be turning the car off or let it idle for a minute or 2 after you get done boosting and you park it.

 

oh I know, I let it idle for about a minute then shut it off.
Don't worry

 

ok just figured i would mention it

 

Alright, I tried the airbox thing, didn't work, no big deal.

But I did get new plugs! Now it will start when hot, just takes a couple more cranks, and it idles pretty decent after a hot start, just a little bit of surging between 7-800rpm, could just be the crappy 2 year old gas and most likely dirty injectors also. I'll throw some fuel injector cleaner in there when I get some new gas. I will also drive around the block again tomorrow and try another hot start to see if it is consistent. And I'll check the resistance on the plug wires and make sure they are workin good too.

 

its hot as hell up here in jersey and just the other day the very same problem happended to me left me stuck opened up the air box pulled out the filter <which was new> cranked it and she sruggled for a sewc then fired up awaiting hks from mazdatrix now 88t2

 

my idle use to surge to but i cleaned my bac valve and it no longer does that... so i suggest you should clean your bac valve too for the hell of it

 

k sounds good, I'll clean the BAC too.

 

Tried the hot start again today, didn't want to start this time, its getting pretty close but not quite. I'll try the other things and see what happens.

 

, no, leave the filter in or it wont start, just take off the top part of the box.

 

I've started it without the filter before, it runs just fine?

 

hmm, my car dies without the air box hooked up lol. The hks filter fixed that and any hot starting problems i had.

 

no I took the top of the airbox off and took the filter out, the bottom of the airbox with the AFM is still hooked up.

Anyway I tried ANOTHER hot start and it started after a couple extra cranks this time, It may have been because it was cooler outside though. It was probably only 70F outside vs. the last time I did it when it was probably 85F.

 

Ok here's a big update:

I recently...

Removed: MOP, ACV and ACV Silencer, EGR Valve, unused solenoids (Yellow, Blue, Gray, Orange), Air Supply Valve, Air Bypass Solenoid Valve, Sub-Zero Start Assist System, useless brackets

Replaced: All the vacuum hoses (only 4 now), fuel lines, coolant hoses, pulsation damper (banjo bolt)

Did the TB mod, grounding, cleaning, etc.

I still have the BAC and I tested it, according to the FSM tests it is working, and I have witnessed it working when the car was wanting to stall and the BAC shot the RPM's back up.

Now, once I got it back together, I went and drove it around, came back, tried to hot start it, STILL would not start. But my dad noticed it was blowing black smoke while I was trying to start it... soo it seemed that the fuel injectors may be leaking. To test that theory, I did the unflood procedure and then tried to start the car. That worked, the car started and wouldn't idle on its own for about 30 seconds, but after that it was fine.

Today, I checked compression and timing. Timing was set correctly.

Compression

Cold engine:
Front rotor - even bounces of 80psi / 95psi if built up to maximum
Rear rotor - even bounces of 60psi / 80psi maximum

Hot engine:
Front rotor - even bounces of 70psi / 85psi maximum
Rear rotor - even bounces of 55-60psi / 70psi maximum

Now that leads me to believe she's not doin too good, but then again, after I checked the compression with the EGI fuse out, I put the spark plugs back in and the car started right up, no idle problems at all. And the car had only been sitting there for 5 minutes while we were checking the compression. Usually it would take the car at least 20-30 minutes before it would start again. That makes me think the injectors are definitely the problem. Or at least something to do with fuel.

Also:
Water Thermo sensor is good
Air Temp sensor is good
Pretty sure there's no vacuum leaks

 

Ah yeah, I think I'll try the whole unplugging the fuel pump to shut the car off when its hot then plug it back in and try to start it deal. I'll do that tomorrow.

 

Holy God! I dumped some Redline fuel injector cleaner in the tank a couple days ago, and now it seems to have fixed my problems, because I haven't touched anything else!

Today I hot started it 4 times:

----Drove around---
1. 3 tries to start, got REALLY close to starting the first 2 times, idled fine after starting
----Drove around----
2. 10 minutes later, started first try, idled fine
----Washed car----
----Drove around----
3. 45 minutes later, started first try, idled fine
----Drove around----
4. 10 minutes later, started first try, idled fine

I boosted at least once each time I drove around. X minutes later means how many minutes since the last time I started it, each time I got back I turned it off then tried to start it 30 seconds later. I drove around for about 5-10 minutes each time.

 

It must be fun talking to yourself

 

ummmm 55 compression in rear rotor sounds like your rear rotor is about to give theres something wrong with that even when my N/A was hot because lack of water =/ i did a compression check to make shure nothing got damaged and i had around 85 and was still ok.....
TwEaK

 

I think its time for a rebuild due to the low comp. and also new injectors or get the old ones cleaned.Just my two cents.

 

i have a guestion if i have 99 psi on the front rotor and 80 85 psi on the back is my motor still good i have a 87 tII

 

I think the difference in compression isnt supposed to be more than 15 between the two rotors, but dont quote me on that.