Jump to content
The mkiv Supra Owners Club

Its finally happened


Robert
 Share

Recommended Posts

well as some of my know, my friend had a supra and wasent looking after it very well....some of you might remember this thread:

http://www.mkivsupra.net/vbb/showthread.php?t=51764

 

 

Anyways he came down to me this morning says the cars smoking and he has no boost at all. When he arrived i told him to drive down a private road and there was so much white smoke pouring out the back i couldn't see where he went, also i couldn't hear any turbo or BOV noises. There was so much white smoke comming out of that car it was so bad! we did a compression test and the results are:

 

200, cyclinder 1

190, cyclinder 2

185, cyclinder 3

190, cyclinder 4

180, cyclinder 5

187, cyclinder 6

 

I took a drive in the car and there was no power and it kept shaking over 2000rpm.

 

I also took a reading from the OX1 port and it was between 0.23v-0.25v, so i take it its running lean on warm idle.

 

 

The car sounds rough and is smoking badly.

 

anyways a lesson to be learnt and that is when i say change the oil and dont rev on a cold engine then do it!

also there was oil in all the pipes and i mean alot.

Link to comment
Share on other sites

im hoping to buy the car off him so i can fix it, i hated when he bought the car because i knew he would drive it the way he did his rover. I really am shocked at the amount of smoke i saw comming out, it was a fresh import and no service history but he never changed any fluids or belts. I dont support the way he acted towards his car its such a shame to see a supra in that state, but thought i would post up about it as it will let new members know how much damage can be done if you dont care or look after your supra.

Link to comment
Share on other sites

Sorry to disagree but it doesn't sound like blown rings with those compression numbers nor from the other symptoms. More likely he blew off one of the hose/pipes between the turbos and the intake manifold. Probably at the X-over pipe. This would account for the rough running, lots of smoke and the low O2 sensor readings which indicates running rich (not lean). AMHIK If he blew a piston or the rings the compression would be way low. The oil in the air box is probably either due to another problem or too much oil used on a foam or cotton mesh after market filter.

 

derek

Link to comment
Share on other sites

its a j-spec and we checked all the pipes around the back of the turbos to the IACV etc and they all looked fine. It has the stock jap spec air box and toyota panel filter fitted. I doubt the amount of smoke it was not because it was running rich, i cant stress how much smoke it was, it was pure white smoke although it had a tint of blue when he drove off.

Link to comment
Share on other sites

I corrected myself in the second message where I stated that the O2 sensor reading low means lean condition. Here is what I believe happens: as the throttle opens up air is drawn into the engine but if the hose is blown off the engine sucks some of the air in after the MAF (or speed density sensor). Fuel is added based upon the MAF or SDS reading which is incorrectly low so the mixture is lean causing misfiring (some fuel does not even ignite) hence the chugging and rough running. Unused fuel from the numerous misfires may be blown out the exaust. Engine will rev with no load but will not run smoothly nor idle. I blew off the crossover pipe and this is exactly the symptoms I had including the smoke.

 

If a set of piston rings are blown the engine will run just not very well until something seizes. IMHO there is no way you can get 170 psi+ compression with blown rings soo something else is wrong.

 

derek

Link to comment
Share on other sites

BTW, the pipes to check are the hoses/pipes (big 2.5") from the turbos to the intercooler across over and up into the intake manifold (not the IACV, or other small hoses). I'll bet one of them is blown off. Very common to blow them off at high boost and get the symptons you saw. Good luck.

 

derek

Link to comment
Share on other sites

I corrected myself in the second message where I stated that the O2 sensor reading low means lean condition. Here is what I believe happens: as the throttle opens up air is drawn into the engine but if the hose is blown off the engine sucks some of the air in after the MAF (or speed density sensor). Fuel is added based upon the MAF or SDS reading which is incorrectly low so the mixture is lean causing misfiring (some fuel does not even ignite) hence the chugging and rough running. Unused fuel from the numerous misfires may be blown out the exaust. Engine will rev with no load but will not run smoothly nor idle. I blew off the crossover pipe and this is exactly the symptoms I had including the smoke.

 

If a set of piston rings are blown the engine will run just not very well until something seizes. IMHO there is no way you can get 170 psi+ compression with blown rings soo something else is wrong.

 

derek

 

Good diagnosis, but as he has a J Spec, he doesn't have a MAF, he has a MAP sensor.

Link to comment
Share on other sites

If it's white and blue smoke and you aren't getting any power then it's probably the turbos gone. The lack of maintenance and oil changes would gum up the oil feed in the bearing area and the bearings would overheat, grind metal, and fail. This failure would probably cause coolant (white) and oil (blue) smoke, and lots of it, because the bearing jacket has both of those plumbed in. Are you losing coolant? Does it smoke on idle? Does it smoke on revup and/or overrun?

 

I'll buy the car off him for a grand ;)

 

-Ian

Link to comment
Share on other sites

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.

 Share

×
×
  • 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.