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-   -   Another FD start issue (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/another-fd-start-issue-1165312/)

Redbul 03-11-24 10:10 PM

You are carrying a fire extinguisher with you, right?

Xion 03-11-24 10:15 PM


Originally Posted by Redbul (Post 12595891)
You are carrying a fire extinguisher with you, right?

yes a small one and not sure if it’s rated for electrical fires, I also have 3 gallons of water with me if that will help

Xion 03-16-24 05:53 PM

GOOD news everyone,


took her out for a much longer drive today and her first proper drive in months and gave her gas. By the time I came back, there was very little to no smoke coming from turbos. So I guess it’s safe to say they were just burning off excess oil from when I overfilled it.


now next question. I get 15psi oil pressure at idle. Isn’t that too low? Also I definitely have an oil leak driver side somewhere (maybe oil pressure sensor etc) so idk if that’s causing oil pressure to be low. When I give it gas it goes up to 60ish psi max

Driver side oil leak didn’t concern me as much because there’s only like four things that could leak, the overfill line that goes to turbos (doubt it), oil filter pedestal, oil fill neck, or oil pressure sensor right?

Redbul 03-16-24 07:24 PM

Is your oil pan bashed up? On my car it was and it pressed against the oil intake screen. I never got over 60 psi.

Is there excess noise inside your engine front cover? Indicating some issue with the oil pump?

Maybe change out the oil filter? make sure it is a proper one for FD.

scotty305 03-16-24 09:53 PM

If you have a leak, I would focus on finding and fixing that immediately. If you're reading oil pressure using the factory sensor, it's probably not showing accurate readings at idle or low RPM. Here are a couple of discussions where people have described that the factory sensor isn't very accurate.
https://www.rx7club.com/general-rota...blems-1156509/
https://www.rx7club.com/3rd-generati...-temp-1153903/

Some people claim that replacing the sensor (sending unit) can fix the problem. Personally I added an aftermarket sensor, and now my aftermarket ECU can keep track of the measurements and trigger rev limiters if the oil pressure is too low. I tried cleaning the original sensor and that didn't seem to help.

Xion 03-17-24 12:53 AM


Originally Posted by Redbul (Post 12596377)
Is your oil pan bashed up? On my car it was and it pressed against the oil intake screen. I never got over 60 psi.

Is there excess noise inside your engine front cover? Indicating some issue with the oil pump?

Maybe change out the oil filter? make sure it is a proper one for FD.


no noise, oil filter is pretty new less than 500 miles on it. Oil pan isn’t bashed up, I have a brace on it, but I think it might be leaking because some of the bolts on there were hand tight, are they supposed to be? I didn’t put brace on

Xion 03-17-24 12:54 AM


Originally Posted by scotty305 (Post 12596386)
If you have a leak, I would focus on finding and fixing that immediately. If you're reading oil pressure using the factory sensor, it's probably not showing accurate readings at idle or low RPM. Here are a couple of discussions where people have described that the factory sensor isn't very accurate.
https://www.rx7club.com/general-rota...blems-1156509/
https://www.rx7club.com/3rd-generati...-temp-1153903/

Some people claim that replacing the sensor (sending unit) can fix the problem. Personally I added an aftermarket sensor, and now my aftermarket ECU can keep track of the measurements and trigger rev limiters if the oil pressure is too low. I tried cleaning the original sensor and that didn't seem to help.


what should normal idle pressure be?

Redbul 03-17-24 03:47 AM

There is a risk if the pan bolts are over-tightened they will crack the housing. Best to read up on that specifically in the FSM.

Oil pan leaks can be tricky to deal with. Probably lots of threads on that.

DaveW 03-17-24 07:40 AM


Originally Posted by Xion (Post 12596395)
what should normal idle pressure be?

That depends on the oil viscosity, synth v non-synth, how hard you were just running (oil temp), and idle RPM. What oil are you using? With 10W30 Valvoline non-synthetic, my idle (750 RPM) oil pressure is usually anywhere from ~15 to 30 psi depending on the variables in my 1st sentence. It's been at that level since new.

These are from my OE (1993) sender and gauge, which is not very precise, especially at low pressures.

Redbul 03-17-24 11:33 AM

Page D-6 of the FSM states 50 p.s.i. minimum.


In later RHD FD the oil pressure gauge was replaced with a boost gauge. A warning light was retained. I installed a $15 oil pressure gauge from the automotive store in my lower single DIN pocket location. It is fed from an adaptor below the oil filter and small tube actually running to the gauge in the dash. At idle it shows about 60psi and driving it pins out at the gauges limit of 90 psi. After a long run yesterday, I notice that the gauge is filing with a small amount of oil. It served me well enough for eight years, but it looks like I am going to have to take my dash apart.:egrin:

DaveW 03-17-24 11:35 AM


Originally Posted by Redbul (Post 12596424)
Page D-6 of the FSM states 50 p.s.i. minimum.

At 3K RPM...

Page D5 of my factory 1993 manual:
4. Run engine @ 3K RPM, note OP gauge reading.
....Oil Pressure: 340 KPa, 50 psi min

No mention that I could find of any min pressure at idle.

Xion 03-23-24 06:38 PM

Ok based on what you guys said, my oil pressure is fine.


so update,

im getting smoke from turbos again. This time it was never overfilled, hell, it’s not even at full about halfway on the dipstick.

was pretty heavy smoke, also to note that this is the first time I drove the car again after a week or two.

the smoke had stopped before the last time I drove it but it came back.

this time though, I had rerouted the line that goes from the bottom nipple on the oil fill neck to a catch can that’s vented, maybe that’s why it’s smoking? I don’t think so as the OEM configuration just takes any oil from the oil fill neck and sends it to the front elbow on the primary turbo.

Redbul 03-23-24 08:10 PM

Can you see more precisely where the smoke is coming out of the turbos?

Are you seeing any oil residue in your upper y-pipe/crossover pipe to the intercooler? (is it new or from before?)

Did you say before you saw a puddle of oil in the front turbo housing/snail?

Is the pool back?

If yes, and you have the breather hose no longer connected, then where is the oil pooling from?

It seems there may be a slow leak inside the turbo which builds up while the car sits.

If the smoke is coming from the oil burning off on the outside of the turbo, you need to identify where the oil is coming from.

Did you check your main seal, afterall?

Put a sheet of cardboard under the car and see if any oil is dripping.

Xion 03-23-24 09:00 PM


Originally Posted by Redbul (Post 12597155)
Can you see more precisely where the smoke is coming out of the turbos?

Are you seeing any oil residue in your upper y-pipe/crossover pipe to the intercooler? (is it new or from before?)

Did you say before you saw a puddle of oil in the front turbo housing/snail?

Is the pool back?

If yes, and you have the breather hose no longer connected, then where is the oil pooling from?

It seems there may be a slow leak inside the turbo which builds up while the car sits.

If the smoke is coming from the oil burning off on the outside of the turbo, you need to identify where the oil is coming from.

Did you check your main seal, afterall?

Put a sheet of cardboard under the car and see if any oil is dripping.


Oil doesn’t seem to be dripping, it doesn’t drip passenger side where the turbos are at all, it used to drip driver side on the front and I think that was from the breather tube that connects to the lower nipple on the oil filler neck. Since I changed that to the catch can, it doesn’t drip. Also my catch can has 0 oil in it. Wait now that I’m thinking about it, maybe the oil is backed up in the line that goes to the catch can? Because the line isn’t routed straight down, it kinda goes up and to the edge of the driver side firewall. So I’m relying on pressure to help move the oil there. I was thinking of routing it back the way it was even though it caused a driver side leak albeit small. I also thought about eliminating my pcv valve and routing that top nipple to my catch can too. Maybe pcv is bad? I doubt it since it’s only like 2-3 years old with max 500 miles on it. Not sure if a bad pcv can cause turbos to smoke either. Actually, I guess it could since if it’s not venting crankcase pressure then oil rises in the oil filler neck and exists to the front turbos to burn off. However, my oil line isn’t even connected to the front turbo anymore and if crankcase had pressure, it’d be venting it to the catch can

other than that I think it could be a bad inner turbo seal that slowly leaks over time and builds up in the turbos. I haven’t checked the main seal, also I never checked to see if there was a puddle of oil in my primary turbo snail, I simply just ran it until smoke cleared up and went away and thought that was the issue.

Redbul 03-24-24 12:33 AM

Where is the smoke coming out of the turbo though?

How do you know it is your turbos smoking?

If your oil level is below half way on the dipstick hash marks, I think it is highly unlikely oil is rising in your filler neck to go either into the PCV valve line or the catch can line.

You could try detaching the line from the catch can nipple and have the breather hose just vent to the floor.

See what comes out.

It was Dale that mentioned the oil pooling in the snail.

I don't know how you can see that.

I am not sure what you can see by pulling off the downpipe.

Or if you take off the front intake elbow whether you can see past the impeller blades.

Or maybe just the oil would be spilling out past the blades?






Redbul 03-24-24 12:42 AM

Is there any oil dribbling out below the impeller?

https://cimg6.ibsrv.net/gimg/www.rx7...bce3b6f949.jpg

Redbul 03-30-24 09:34 PM

Another possibleoil leak source:

My friend blew his motor a few weeks ago and just pulled it an disassembled it this afternoon. This gave me a chance to look more closely.

I noticed that the source of oil for the turbo feed comes from a banjo bolt at the top right (as you face it) of the front plate. (See ciircle on diagram one>

The metal line runs down toward the turbo (of course) but it intertwines with the metal line that connects with the breather tube, as they run in the same direction.

If you have a leak at the bajo bolt the oil could dribble down the outside of those intertwined pipes.

It seem to me..




https://cimg6.ibsrv.net/gimg/www.rx7...e3d5c867fe.jpg
https://cimg8.ibsrv.net/gimg/www.rx7...40d1551a9c.jpg


[A word of caution regarding sealing the oil pan. It seems that my friends engine likely failed because the oil
uptake screen had become clogged with excess sealant used when someone reattached the oil pan.]


Redbul 03-30-24 09:41 PM

https://cimg9.ibsrv.net/gimg/www.rx7...5a65ac5eef.jpg
Banjo bolt is partially obscured by the rubber house in front of it.


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