Jump to content
The mkiv Supra Owners Club

Misfire


jjs_82

Recommended Posts

Had the car out for a quick blast today, and all of a sudden she went off a cylinder. Got her back to the house and the white smoke coming from the exhaust and petrol spraying out of it. So, I went and took the plugs out checked them one by one the cylinder number 6 is filled with fuel. I had to unplug the injector at that cylinder in order for her to stop pouring the fuel out of the exhaust. She's a single turbo running 850cc injectors, as of the minute she is only running on 5 cylinders, any one have any idea what it could be?. No bad noises coming from the engine or anywhere. 

Link to comment
Share on other sites

Well, if you have confirmed a spark then there is a good chance you have a leaking injector flooding the cylinder and causing the misfire. There is no easy way to get to test that so its socket time. Just as well its the weekend. You could try an injector cleaner in the fuel feed as an outside chance of saving you the strip down time which may work if the injector is just stuck/sticking.

Link to comment
Share on other sites

11 minutes ago, rider said:

Well, if you have confirmed a spark then there is a good chance you have a leaking injector flooding the cylinder and causing the misfire. There is no easy way to get to test that so its socket time. Just as well its the weekend. You could try an injector cleaner in the fuel feed as an outside chance of saving you the strip down time which may work if the injector is just stuck/sticking.

Thanks for the reply.  What about valves?

Link to comment
Share on other sites

Get a testlight or multimeter on injector plug 6 and see if ECU injector signal is constantly grounded, compared to the other injectors. Could be that you have some bad wiring that is shorting somewhere and causing injector to stay open all the time. If this is the case run a new wire from ECU to injector and see if problem goes away. 

You can also log into Syvecs on your PC and perform an output test of all your injectors. See if all the injector solenoids sound the same whilst testing, if 6 sounds different then could be a mechanical failure of some sort. 

Link to comment
Share on other sites

So one of two things then:

a) The injector driver on the ECU has failed and is sticking on (though I've never seen this happen myself)

or 

b) Wiring has a split or fault, causing it to earth out constantly. 

Run a new wire from injector pin on ECU to the injector and see if issue goes away.  

Link to comment
Share on other sites

24 minutes ago, jjs_82 said:

Thanks for your help. 

I take it you just can't plug in and clear a fault like a normal ecu. 

You can, but there won't be any fault that causes #6 injector driver to stay grounded. Not to my knowledge at least. Smells like a hardware problem to me. Either way I'm sure Syvecs Support can point you in the right direction. 

Link to comment
Share on other sites

10 minutes ago, Mike2JZ said:

You can, but there won't be any fault that causes #6 injector driver to stay grounded. Not to my knowledge at least. Smells like a hardware problem to me. Either way I'm sure Syvecs Support can point you in the right direction. 

OK. I'll have to give them a call tomorrow. 

Link to comment
Share on other sites

  • 2 weeks later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. You might also be interested in our Guidelines, Privacy Policy and Terms of Use.