Help! Post-rebuild engine problems!

86.5supra · 10-24-2009, 03:05 PM

your getting a fuel cut out my 7mgte did it after we had it rebuilt. after they tore the motor back apart we found out that it was a O2 sensor that was fucking up the computer.

CanadianBak'inSupra · 10-24-2009, 03:53 PM

Quote:

Originally Posted by 86.5supra

your getting a fuel cut out my 7mgte did it after we had it rebuilt. after they tore the motor back apart we found out that it was a O2 sensor that was fucking up the computer.

not tryin to topic steal, but how many sensors does the engine have (for a non turbo)
i wouldnt mind getting all mine checked

ricerbaby · 10-24-2009, 06:24 PM

having the same problem at the moment.. my 88 is doing the same thing. it sounds just like a computer problem, i had a broken coolant hose and it threw coolant and water all over the engine and it got in my cpu which made my car do the same thing. a new cpu unit is pretty expensive... but you can look for one on ebay too...

cre · 10-24-2009, 11:08 PM

What the OP is referring to is generally known as "limp mode". It's a base setting which is used in the event that a critical problem is detected. Often it's not really something big, an unplugged sensor, a leak,

Check for error codes, check the TPS' alignment, inspect all of the intake plumbing for holes/cracks/or other leaks, make sure the AFM harness plug is connected firmly to the AFM, check the knock sensors and their wiring.

A bad O2 sensor may cause you to run a bit rich or a bit lean but anything too far out of range and the ECU stops reading the O2 sensor altogether and reverts to the stock fueling maps... Also, at WOT, the ECU doesn't even read the O2 sensor; so, if you've got problems at WOT it is definitely something else.

One other possibility is that the timing belt skipped a tooth or wasn't properly installed causing uneven tension which when the motor is finally turned over puts the pulleys out of sync.

cre · 10-24-2009, 11:11 PM

Quote:

Originally Posted by ricerbaby

having the same problem at the moment.. my 88 is doing the same thing. it sounds just like a computer problem, i had a broken coolant hose and it threw coolant and water all over the engine and it got in my cpu which made my car do the same thing. a new cpu unit is pretty expensive... but you can look for one on ebay too...

In your case it very well may be the ECU. Try cleaning out ALL of the harness connectors behind the dash with electrical contact cleaner (Radio Shack carries it as well as most electronic supply shops). If the problem remains another ECU may indeed be in order. What are you driving? N/A or Turbo, Manual or Auto? I have another GE ECU which I know is good.

CanadianBak'inSupra · 10-25-2009, 03:57 PM

i just did my ecu
guy crashed his 89 7mge and i got his ecu for the lowball price of 40 dollers
if you need help on getting it in its still fresh in my mind...

Tony · 10-26-2009, 04:46 AM

It's a turbo manual.

Crank and cams are timed right, popped off the timing cover and looked (cover off in the vid)
Cam position sensor adjusted... there is separate ignition timing? I'll have to look that up in the TSRM, I thought it was just the CPS.

I think it didn't fire on all cylinders with the BHG, so i'll have to have the ECU checked... the check engine light has never been on... but who knows.

The knock sensors... I didn't know what those were until I looked them up... they are at the bottom of the upper intake manifold, with vacuum lines running through them... so they're all squared away right.

Ugh after dropping 2k AFTER purchase of the car into this thing, I need to be slapped for not getting a 1jz... but I was a noob then.

Haha one of you should just drive here and plug in the thing I missed so it'll run lol.

ricerbaby · 10-26-2009, 10:09 PM

Quote:

Originally Posted by cre

In your case it very well may be the ECU. Try cleaning out ALL of the harness connectors behind the dash with electrical contact cleaner (Radio Shack carries it as well as most electronic supply shops). If the problem remains another ECU may indeed be in order. What are you driving? N/A or Turbo, Manual or Auto? I have another GE ECU which I know is good.

it has a turbo. the coolant hose was connected to the turbo. it is also an auto transmission. i have it at a reliable shop at the moment working on the problem, but they arnt sure exactly what the problem is, if it is the GE ECU how much would you be willing to give that up for?

cre · 10-27-2009, 01:06 AM

If it's a 7M-GTE the ECU I have won't work for you. I'd want $50 including shipping.

You don't want to know how much I have invested/dumped into my car...

and it's still slow and ugly.

Tony · 10-28-2009, 09:21 PM

for sale!

http://fortwayne.craigslist.org/cto/1441741517.html

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
7MGE Engine rebuild	oregonjoe	MKIII Supra	69	03-23-2010 02:12 AM
7MGE Engine Rebuild	SilenceboneSupra	MKIII Supra	1	10-23-2007 06:45 PM
PLEASE help newbee with engine rebuild	canadian mole	MKIII Supra	4	06-17-2007 01:01 AM
1988 supra engine rebuild	1988Suprakid	MKIII Supra	5	06-07-2006 09:07 PM
New Engine Or Rebuild Help ! ! ! ! !	DarkRaiderz	MKIII Supra	5	01-23-2006 01:21 AM

10-24-2009, 03:05 PM	#1
86.5supra 3" Exhaust Join Date: Jun 2009 Location: ny Posts: 83	your getting a fuel cut out my 7mgte did it after we had it rebuilt. after they tore the motor back apart we found out that it was a O2 sensor that was fucking up the computer.

10-24-2009, 06:24 PM	#3
ricerbaby Stock Join Date: Oct 2009 Location: flower mound texas Posts: 7	having the same problem at the moment.. my 88 is doing the same thing. it sounds just like a computer problem, i had a broken coolant hose and it threw coolant and water all over the engine and it got in my cpu which made my car do the same thing. a new cpu unit is pretty expensive... but you can look for one on ebay too...

10-24-2009, 11:08 PM	#4
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	What the OP is referring to is generally known as "limp mode". It's a base setting which is used in the event that a critical problem is detected. Often it's not really something big, an unplugged sensor, a leak, Check for error codes, check the TPS' alignment, inspect all of the intake plumbing for holes/cracks/or other leaks, make sure the AFM harness plug is connected firmly to the AFM, check the knock sensors and their wiring. A bad O2 sensor may cause you to run a bit rich or a bit lean but anything too far out of range and the ECU stops reading the O2 sensor altogether and reverts to the stock fueling maps... Also, at WOT, the ECU doesn't even read the O2 sensor; so, if you've got problems at WOT it is definitely something else. One other possibility is that the timing belt skipped a tooth or wasn't properly installed causing uneven tension which when the motor is finally turned over puts the pulleys out of sync.

10-25-2009, 03:57 PM	#6
CanadianBak'inSupra Official hall monitor / search nazi - NO SOUP FOR YOU! Join Date: Oct 2009 Location: Canada, BC Posts: 837	i just did my ecu guy crashed his 89 7mge and i got his ecu for the lowball price of 40 dollers if you need help on getting it in its still fresh in my mind...

10-26-2009, 04:46 AM	#7
Tony Stock Join Date: Aug 2009 Location: Indiana Posts: 15	It's a turbo manual. Crank and cams are timed right, popped off the timing cover and looked (cover off in the vid) Cam position sensor adjusted... there is separate ignition timing? I'll have to look that up in the TSRM, I thought it was just the CPS. I think it didn't fire on all cylinders with the BHG, so i'll have to have the ECU checked... the check engine light has never been on... but who knows. The knock sensors... I didn't know what those were until I looked them up... they are at the bottom of the upper intake manifold, with vacuum lines running through them... so they're all squared away right. Ugh after dropping 2k AFTER purchase of the car into this thing, I need to be slapped for not getting a 1jz... but I was a noob then. Haha one of you should just drive here and plug in the thing I missed so it'll run lol.

10-27-2009, 01:06 AM	#9
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	If it's a 7M-GTE the ECU I have won't work for you. I'd want $50 including shipping. You don't want to know how much I have invested/dumped into my car... and it's still slow and ugly.

10-28-2009, 09:21 PM	#10
Tony Stock Join Date: Aug 2009 Location: Indiana Posts: 15	for sale! http://fortwayne.craigslist.org/cto/1441741517.html