I would like to share something I noticed when I installed my magnus intake manifold...

When I cracked the throttle body during removal of the stock intake manifold it had an extremely strong fuel odor. I noticed it while just opening the throttle plate to take off the cable...I wasn't smelling around.
This leads me to think more and more that the injectors are leaking during shutdown.

 

its strange that the evo seems to be the only application with this sort of problem though?

I would be curious to know how the Honda, Subaru, and/or Toyota cars that run these have for bleed own pressure etc after shutdown - it could be a def. mechanical issue among the evo that causes this to happen but not on the "other" cars.

I just cant see us all having leaking injectors and only a few get lucky when other vehicles dont experience anything related and I am sure more have been sold on the honda side than any other? - unless of course there is something with the evo that forces/causes this condition? All speculation of course - but I would still say the problem is the application causing the issue and not the injector itself? but seems FP is a possible cause..

If this isn't solved by next spring i will get the adapter and FP gauge on 0xDEADS car and see how his FP bleeds down, etc after shutdown. Only real way we will know is to be able to see what is happening on a car that is not experiencing any issues....(only reason i say spring as his car is officially put away for winter)

 

I do not believe in this leaky injector theory. The injectors are dry in the rail upon removal in our tests. The cylinders are also dry when the plugs are pulled. It is a fuel pressure induced issue.

 

I have ordered the ID1000 for my evo ix with a Autronic SM4. As soon as they arrive I will install them and let you know if I get the same problems.

 

I have no such problem with my Motec.

 

I've been able to get noticeable changes in the starting conditions by changing the cranking enrichment related parameters.

I can make it take any where from 4-5 seconds of cranking all the way up to 10-15 seconds by changing the parameters. The only problem though is it's not a quick process to evaluate the changes as you have to wait 10-15 minutes for it even show those characteristics again. Also, it's not real consistent. A change that seems to make a big impact doesn't always consistently have the exact same response. I've also just passively been messing with it as I have tuned other things.

I have not gotten the problem to go away though.

One more data point though, a co-worker had these injectors in his Subaru. He had a starting issue where if it didn't fire the first rotation or so, it would sputter then take a good 10 seconds or so to start. He said it was pretty sporadic though and like 1 out of 5 times starting it would do it. Couldn't remember if it was warm or cold starts that it did it either and has since sold the car.

 

Depending upon where the crank comes to rest upon shutdown you'll have at least 3 cylinders with their intake valves closed.... and fuel will not enter those combustion chambers... FURTHER more why in the hell would the fuel be on the spark plugs if the injectors were leaking? It would run past the seat onto the CC and then onto the cylinder walls/piston.

 

let me hold the two apart, R/T I think they were looking/ smelling into the cylinder through the plug hole.


I can referee because I have respect for both parties.

 

If you read what you quoted you will realize we stated the pistons were dry and you replied, there will be fuel on the pistons with leaky injectors.

The injectors are not leaking. There is too much pressure in the rail and not enough voltage to open them at startup with high pressure. Period.

 

If the fuel runs down the cylinder wall then it will end up on the rings.... and then the oil pan. Not necessarily the top of the piston.

I however think that it would vaporize long before it could "pour" it's way to the piston. Most likely evaporating on the back of the intake valve...

 

If they are leaking, it isn't a gushing leak because my FPR holds pressure for a very long time. As R/T said, the fuel is most likely vaporizing if the injectors are leaking.

 

okay.. so i got three pages into a crapfest of arguing and skipped right to posting. i can't take any more of this reading. :P .... what i'm wondering is: do these injectors work better than, say, RCs at stock FP?
i'll be running a stock IX engine with 264 cams, springs/retainers, cone filter, walbro/buschur pump, 3" TBE, port-matched mani/O2, and 3" TP, BBK Full turbo.

i'm hoping for 350-400whp on 91. i would like my car to idle like stock. now.. i've dealt with hondas for years and know that getting 1000cc injectors to idle is HARD. so.. these are better?

 

IF it were not for my cams the idle on my bbk'd VIII would be fine.

My cold start/warm start is good. however, people are having an issue, I don't know, nobody does, what the issue is. It could be something as simple as a battery connection/ grounding kit, who knows.

 

gotcha. something i'll have to think about. when i had my honda, these were the way to go. no doubt. but on my mitsu... i just don't know.

it's not my DD... so i guess i can deal with some issues here and there.. but start up problems are embarrassing at meets.
LOL
does this thread include a link to how to bypass the resistor box? i'm at work.. slooooow connection. i tried to search and saw nothing.
then i guess i need to find the injector adapters?

 

These injectors don't start any worse then an AEM...

How about that...

IF it is a voltage issue, then if we could get a person that has the problem in connection with either a power supply or one of those voltage boosters from Fuel Injector Clinic, it would sort it out pretty quickly.