It lives! (but no tach :/ )

[Fran Hall RCR]

Jack.
Thats what I was eluding to also...but starting with the coilpacks and then expanding to the injector harness...one step at a time..

 

[Jack]

Exactly!

 

[Alex]

O2 sensors can be sensitive to damage from being dropped, do you have a solid connection to/from the o2 sensor wire to the sensor, that extra bung you have is it before the O2 sensor - is it leaking. Are all your Intake/TB connections properly connected and/or plugged.

Solid connection, tuning bung is after the others and properly plugged.

Intake and throttle throttle body connections are all proper, as far as I know. Perhaps somebody could confirm this is correct:

- brake booster on back of intake manifold - plugged
- port on right-hand side of throttle body - plugged
- port coming out of passenger side valve cover - connected to air intake tube after maf but before throttle body
- port coming out of valley cover connected to left-hand side of throttle body
- rear driver side valve cover port plugged

Dumb question, but when you reversed the intake manifold did you maintain the coil packs and injectors on the proper sides of the engine. They don't move, only the manifold proper.

Yes ... just popped the intake manifold off, flipped him around, and bolted him back up, didn't touch anything else .... if i had flipped other stuff I'm pretty sure the engine would run like piss because the firing order would be off.

 

[Ken Roberts]

The port coming out on the right side behind the throttle body is the one that connects to the valley cover.
The left side port is the one for the EVAP that gets plugged if not using.

Not a big mistake though. They are both just vacuum ports behind the throttle body.

An exhaust leak before the oxygen sensor can severly affect the O2 readings on that bank.

Alex I'd swap coil packs from one side to the other for a test.

 

[Alex]

The port coming out on the right side behind the throttle body is the one that connects to the valley cover.
The left side port is the one for the EVAP that gets plugged if not using.

Not a big mistake though. They are both just vacuum ports behind the throttle body.

An exhaust leak before the oxygen sensor can severly affect the O2 readings on that bank.

Alex I'd swap coil packs from one side to the other for a test.

are you sure about the ports because in Dean's thread you said the opposite

http://www.gt40s.com/forum/366462-post144.html

I've got #3 (left side of throttle body, with intake manifold reversed) connectd to #5 (valley cover) and #1 (right side of tb, w/ intake manifold reversed) plugged

Headers are bolted on tight, no signs of leaks around them. I do have a Burns 4 into 4 slip fit connection before the O2 bungs on each side, but they're clean ... no steam coming from them and no exhaust crap spit out from them


I'm pretty sure this is open/closed loop related (so some very weird mechanical problem). Here's what I've found

- Car is cold; start car, exhaust pulses on each side are even and strong. Each side you can evenly hear the cam going thump thump thump

- Car warms up (e.g., 180*) everything is fine.

- Car gets to 195* (plus or minus a few) the exhaust pulses on the passenger side immediately stop and it becomes abreeze of air, not a strong pulse. Also, the cam sound stops on the passenger side....you can hear it strongly on d/s, but not passenger

- turn car off, wait a few seconds, turn it back on, no different - weak exhaust pulse on passenger side (just feels like a gentle breeze of air, not a strong push out) and no cam sound. Almost liek the cylindres arn't firing

- turn car off, wait 5-10minutes. Water temp drops from 195* to 170ish (for example). Start car, everythign is good - exhaust pulses even and strong, I can hear the cam sound. Stand behidn the car and when the dash reads 195 the exhaust pulses stop form the passenger side and the cam sound stops as well. It's almost like the passenger side isn't firing, even though it is.

- turn car off, turn back on, same story.

- turn car off, wait 10 minutes for temps to drop 10-15*, turn car back on, everything is good until the dash reads 195 again.

i can't see this being mechanical - if it were a case of the engine heating up and loosing compression (or something) why would waiting 5-10minutes make it better. Once warm you'd think it would be a constant problem. It's far too suspicious it's always at 195* (which is when the ecu goes into closed loop mode). Never 185 or 190, but 195 according to my dash readout

 

[Ken Roberts]

I consider #3 the right side and you call it the left side. Misunderstanding. You have it installed correctly!

Flip the oxygen sensors Alex. Your passenger sensor might be bad.

 

[Mike]

Just take the "catch" can out of the mix and you'll get one option.

 

[Alex]

Flip the oxygen sensors Alex. Your passenger sensor might be bad.

I did, no difference.

I'm going to try unplugging the o2 sensors and forcing it to open loop because at any temperature other than 195 it works fine. And 195 is when the t-stat open and suspiciously the ECU goes into closed loop.

 

[Dean Lampe]

Since you have 2 bungs in the driver side I would also plug both 02 sensors into the drivers side and the LM1 in the passenger. The reason is that then you know the both sides of the engine are reading the same thing. This will remove any question about exhaust leaks. The lm1 will tell you what happens at 195. It would be interesting to see if the passenger side runs different with the passenger side 02 in the drivers side pipe. I'm still trying to determine if its mechanical or tuning. I'm starting to agree with you about being a bad tune. I just don't think it is very likely, but it is possible.

 

[Alex]

Being the most super awesome race car mechanic ever i figured out the issue - I had plugged the driver O2 sensor into the passenger side and vice versa .... isn't the point of EFI to say 'hey stupid, there's a problem and here's what it is' :/

I miss my magic screws and jets that performed voodoo magic :lipsrsealed:

 

[Mike]

You need to throw a scanner on that motor/ECM and see what is going on.... borrow one from a fellow local motorhead -- they've come down in cost a lot if you have to buy one.

 

[Alex]

You need to throw a scanner on that motor/ECM and see what is going on.... borrow one from a fellow local motorhead -- they've come down in cost a lot if you have to buy one.

See post above yours

 

[Mike]

" it's usually something simple that may reveal itself as a "Duh" moment."... or will the issue now switch to the other bank.... bruhahahaaaaa:shocked2:

 

[Seymour Snerd]

isn't the point of EFI to say 'hey stupid, there's a problem and here's what it is'?

No, I think the point is to inject fuel electronically. :idea:

My favorite comeback to a complaint like this came from a guy who worked on my Lotus Europa. I was fretting about something (wheel centering, I think) and he said "Perhaps you should consider public transit."

 

[Ken Roberts]

Being the most super awesome race car mechanic ever i figured out the issue - I had plugged the driver O2 sensor into the passenger side and vice versa .... isn't the point of EFI to say 'hey stupid, there's a problem and here's what it is' :/

I miss my magic screws and jets that performed voodoo magic :lipsrsealed:

I'm confused....don't both oxygen sensors share the same part number? Why would it matter if you flipped them around?

 

[Alex]

I'm confused....don't both oxygen sensors share the same part number? Why would it matter if you flipped them around?

Not the O2 sensors themselves, but the plug-in ..... driver was reading from passenger side and vice versa.

 

[Fran Hall RCR]

Cetainly sounded to me like something was flip flopped...glad you found it.

 

[Fran Hall RCR]

Certainly sounded to me like something was flip flopped...glad you found it.

 

[Alex]

Certainly sounded to me like something was flip flopped...glad you found it.

I guess I'm basically done now - drive it around the block tomorrow, onto the dyno to get the tune right, replace my springs with the heavier hypercoils (still waiting on them since september, apparently hypercoil is moving factories or something), ride height, caster/camber/toe and cross my fingers nothing falls apart

 

[Jack]

Happy to learn that it was something simple Alex! Can't wait to learn of your drive around the block..

 

[Jim]

I guess I'm basically done now - drive it around the block tomorrow, onto the dyno to get the tune right, replace my springs with the heavier hypercoils (still waiting on them since september, apparently hypercoil is moving factories or something), ride height, caster/camber/toe and cross my fingers nothing falls apart

Video please. :laugh: