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2G Car still won’t start

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98gstJames

Proven Member
215
41
May 25, 2022
WInchester, Virginia
Alright so I’ve been trying to get my car to start and I’ve done a lot, what does it sound like my car is missing now? I’ll add a video, I’m just lost

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Got bad news… not so sure what it is but I hope it’s not what I think. So I finally got the o ring for my car and it put it on, put the thermostat housing on and then I put coolant in the car, plugged my obd2 in to see that the 02 sensor was working and it was, then I went to start the car, it wouldn’t start. I didn’t try to start it anymore bc I was afraid, so I then thought I should pull the plugs to look at them and so I did and when I pulled them out there was coolant on the plugs…I looked down in the cylinders and there is a puddle of coolant in each of them, only way I know this can happen is a blown head gasket but when I pulled the dipstick out there isn’t any coolant mixed w the oil, so I’m confused. Either way it’s a shitty time it seems. It’ll be another thing on the list but I won’t let this stop me either for sure, I can’t give up on the dsm.
Either do a leak down test with the coolant cap off or pressure test coolant system with plugs out. Either will confirm what you may already know.
 
Either do a leak down test with the coolant cap off or pressure test coolant system with plugs out. Either will confirm what you may already know.
Could it be a blown head gasket? Or is there another way coolant can get in the cylinders? Also I’ll have to wait on the leak down test rn I don’t have the tools to do it.
 
Could it be a blown head gasket? Or is there another way coolant can get in the cylinders? Also I’ll have to wait on the leak down test rn I don’t have the tools to do it.
Possible. Here are other ways coolant can enter.
Leaking fiav gasket
Cracked head (unlikely but possible)
Cracked block (unlikely but possible)
If it’s in all 4 cylinders and out of the blue, I would check fiav gasket first.
You can also looping the coolant hoses to the fiav so no coolant passes through it to eliminate this.
 
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Possible. Here are other ways coolant can enter.
Leaking fiav gasket
Cracked head (unlikely but possible)
Cracked block (unlikely but possible)
If it’s in all 4 cylinders and out of the blue, I would check fiav gasket first.
You can also looping the coolant hoses to the fiav so no coolant passes through it to eliminate this.
What is the fiav gasket and where is it located? I wanted to do a compression test on it but I was going to after I had no leaks but the coolant in the cylinders kinda stopped me from trying to start it anymore to do a compression test.
 
What is the fiav gasket and where is it located? I wanted to do a compression test on it but I was going to after I had no leaks but the coolant in the cylinders kinda stopped me from trying to start it anymore to do a compression test.
FIAV fast idle air valve is bolted under the throttle body and has two coolant lines. It allows more air to bypass the throttle body when the car/coolant is cold. Once it warms up, it fully closes the bypass. There is a gasket between the fiav and throttle body. Again, you can loop the lines to eliminate this as your coolant leak

@98gstJames this is a 1g tb & fiav. Green is the coolant passage and the other holes are air passages.
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Got bad news… not so sure what it is but I hope it’s not what I think. So I finally got the o ring for my car and it put it on, put the thermostat housing on and then I put coolant in the car, plugged my obd2 in to see that the 02 sensor was working and it was, then I went to start the car, it wouldn’t start. I didn’t try to start it anymore bc I was afraid, so I then thought I should pull the plugs to look at them and so I did and when I pulled them out there was coolant on the plugs…I looked down in the cylinders and there is a puddle of coolant in each of them, only way I know this can happen is a blown head gasket but when I pulled the dipstick out there isn’t any coolant mixed w the oil, so I’m confused. Either way it’s a shitty time it seems. It’ll be another thing on the list but I won’t let this stop me either for sure, I can’t give up on the dsm.

For water in all the cylinders the FIAV (= Idle Speed Control Valve) gasket is indeed the best bet. It's a complicated molded rubber thing that fits in the grooves on the TB and if an old one is reused and doesn't fit right or if it's left out, you get a leak. Coolant circulates through the ISCV to prevent icing on damp mornings after a cold night -- one of the frequent problems of engines with a carburetor.

I've been tempted to try replacing an ISCV without removing the TB. While in theory this would be possible, the challenge of getting that gasket in the right place without being able to see it kept me from trying -- and now I know why. So ... thanks!

First thing would be to get the fluid out of the cylinders. I'd probably do it with a shop vac but others may have better ideas. If you crank an engine with a liquid in a cylinder there's a real risk of breaking something. After clearing the liquid, turn the engine over by hand just to be double sure.

Then I would follow the other suggestion to use a loop of hose to connect between the supply and return nipples on the engine so the coolant doesn't go through the ISCV. Then get the engine running again and do other tests.

What probably happened is you ran the engine long enough to build up some pressure in the cooling system. Then when it stopped, coolant was forced through some leak into the intake or cylinders. I can only think of the two possibilities -- lots of head gasket leaks or a leak into the TB and then through the intake into the cylinders. The question is just what's leaking and getting the engine just a little warm again with the ISC passage bypassed should answer that.

Starting up with the radiator cap loosened and then removing it for a moment once started will give you bubbles of exhaust gas if there's a head gasket leak.

And of course you've found another problem with your car's idle: Coolant leaking into the cylinders. Try to think of this as unexpectedly rapid diagnostic progress.

.
 
We've been chasing this for awhile now. Refresh our memories. This car was running? You did not overheat it severely?
We've given you the tools to eliminate some suspects. All 4 cylinders? Not likely a head gasket unless you severely overheated it to the point where it died. If you choose to loop the coolant lines you can just turn the car over with no spark plugs in it to blow the coolant out. Pressurize the coolant system and peek in the cylinders. If a leak doesn't present itself I would say fiav is suspect.
 
FIAV fast idle air valve ... allows more air to bypass the throttle body when the car/coolant is cold. Once it warms up, it fully closes the bypass.
That's not entirely right. FIAV/ISCV does give another route for intake air which is under ECU control. The 'fast idle' function --- extra air to give the power to allow the engine to run when it's very cold and idling -- is one of its jobs. It also opens when the driver takes his foot off the accelerator causing the throttle plate to slam shut, admitting enough air to let the engine decelerate to idle speed over a couple of seconds rather than likely stalling -- the 'dashpot function.'

And it also manages the idle speed constantly when the throttle is closed. The standard warm idle for our 2G cars is 850, wired in to the ECU. When the A/C kicks on or a load comes on the alternator or the power steering pump is delivering pressure the ECU is warned and makes an instant correction to the ISCV setting so that the engine speed doesn't dip perceptibly.

For the A/C it speeds up the idle by 100 RPM --- the 'idle up' function -- to improve A/C performance.

I don't think the valve is ever supposed to be completely closed. On 1G cars broken valve pintles are pretty common and the only way I can think of that happening is the valve was trying to keep going past '0' open. The spec for the Expo LRV engines is 2 - 20 steps open when idling without accessory load.
 
So I got the coolant out and did a compression test and cylinder #4 tested at 90 psi,# 3 at 90 psi, #2 at 120 psi and # 1 at 150 psi. Am I correct it’s a head gasket along with the possibility of the fiav gasket?
 
So I got the coolant out and did a compression test and cylinder #4 tested at 90 psi,# 3 at 90 psi, #2 at 120 psi and # 1 at 150 psi. Am I correct it’s a head gasket along with the possibility of the fiav gasket?
You need to do a leakdown test to pinpoint the cause of the failed compression test. I’d do this with a coolant funnel attached so you can look for bubbles leaking into the cooling system, if that’s the problem.
 
That's not entirely right. FIAV/ISCV does give another route for intake air which is under ECU control. The 'fast idle' function --- extra air to give the power to allow the engine to run when it's very cold and idling -- is one of its jobs. It also opens when the driver takes his foot off the accelerator causing the throttle plate to slam shut, admitting enough air to let the engine decelerate to idle speed over a couple of seconds rather than likely stalling -- the 'dashpot function.'

And it also manages the idle speed constantly when the throttle is closed. The standard warm idle for our 2G cars is 850, wired in to the ECU. When the A/C kicks on or a load comes on the alternator or the power steering pump is delivering pressure the ECU is warned and makes an instant correction to the ISCV setting so that the engine speed doesn't dip perceptibly.

For the A/C it speeds up the idle by 100 RPM --- the 'idle up' function -- to improve A/C performance.

I don't think the valve is ever supposed to be completely closed. On 1G cars broken valve pintles are pretty common and the only way I can think of that happening is the valve was trying to keep going past '0' open. The spec for the Expo LRV engines is 2 - 20 steps open when idling without accessory load.
You’re confusing fiav and isc. A proper functioning fiav will completely close when coolant temp reaches a certain temp and is no way controlled by the ecu.
 
We've been chasing this for awhile now. Refresh our memories. This car was running? You did not overheat it severely?
We've given you the tools to eliminate some suspects. All 4 cylinders? Not likely a head gasket unless you severely overheated it to the point where it died. If you choose to loop the coolant lines you can just turn the car over with no spark plugs in it to blow the coolant out. Pressurize the coolant system and peek in the cylinders. If a leak doesn't present itself I would say fiav is suspect.
Yes the car was running before, I’m almost certain I didn’t overheat it but I’m not 100% sure on it bc I didn’t sit there and rev on it or anything like that, alright so basically by closing the loop that is to test the fiav gasket?
 
Yes the car was running before, I’m almost certain I didn’t overheat it but I’m not 100% sure on it bc I didn’t sit there and rev on it or anything like that, alright so basically by closing the loop that is to test the fiav gasket?
Yes. No coolant will flow through the fiav if you loop the lines.
 
Alright I’ll do that then unless I have other issues that are related to the coolant, does the compression test I did give any answers?
The compression are to low the average are 178 PSI
Do the wet test too, drop a bid oil on the cylinder and do the compression test again, if the compression go up you have a bad piston rings
 
FIAV/ISCV does give another route for intake air which is under ECU control. The 'fast idle' function --- extra air to give the power to allow the engine to run when it's very cold and idling -- is one of its jobs. It also opens when the driver takes his foot off the accelerator causing the throttle plate to slam shut, admitting enough air to let the engine decelerate to idle speed over a couple of seconds rather than likely stalling -- the 'dashpot function.'
As mentioned the FIAV and the ISC/IAC are two different things. The FIAV is 100% mechanical based on coolant temps. If you block off the coolant feed to the TB you need to block off the FIAV with a plate or by winding the valve in to block the airflow.

The ISC/IAC is 100% ECU controlled to manage the idle speed and emulate a dashpot.

Coolant isn't going to leak from the ISC/IAC, it can leak INTO it like it can leak into the bypass channel from the FIAV when this gasket fails .

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As mentioned the FIAV and the ISC/IAC are two different things. The FIAV is 100% mechanical based on coolant temps. If you block off the coolant feed to the TB you need to block off the FIAV with a plate or by winding the valve in to block the airflow.

The ISC/IAC is 100% ECU controlled to manage the idle speed and emulate a dashpot.

Coolant isn't going to leak from the ISC/IAC, it can leak INTO it like it can leak into the bypass channel from the FIAV when this gasket fails .

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So if the coolant can leak into the ISC/IAC then into the fiav does it then leak into the cylinders? Should I be getting a new head gasket because of the compression reading?
 
Coolant will make its way into the intake manifold if that gasket is leaking since it shares the same air passage as the isc.

You’ll need to further diagnose why you have low compression in the two cylinders. As previously mentioned, add a cap full of oil to those cylinders and do another compression test. This will tell you if it’s the piston rings since the oil will help seal the piston rings. If that doesn’t bump up compression, you’ll want to do a leak down test. This will tell you where compression is leaking.

To do a leak down test, put that cylinder to tdc with oil cap, dip stick and coolant cap off. Once you start adding air, listen to see where it’s leaking from. Exhaust, oil cap, dip stick and check for bubbles in coolant. Look up leak down test on YT.

Leaking from
Exhaust = exhaust valves
Oil cap = intake valves
Dipstick = piston rings
Coolant = head gasket
 
So if the coolant can leak into the ISC/IAC then into the fiav does it then leak into the cylinders?

Tony mentioned it. Once that gasket fails you're filling the TB with coolant via it's bypass air channels. Any vacuum in the intake manifold will draw it from the TB into the manifold and from there into the cylinders.

This is just a possibility not proof. You reported coolant in your cylinders and you need to track the source down.

While the plugs are out you can clear the cylinders by cranking it or get a wet/dry vacuum. It might time for new plugs too if they are coolant fouled.

Since you were able to see that the O2 worked, what is the ECT reading?
 
Tony mentioned it. Once that gasket fails you're filling the TB with coolant via it's bypass air channels. Any vacuum in the intake manifold will draw it from the TD into the manifold and from there into the cylinders.

This is just a possibility not proof. You reported coolant in your cylinders and you need to track the source down.

While the plugs are out you can clear the cylinders by cranking it or get a wet/dry vacuum. It might time for new plugs too if they are coolant fouled.

Since you were able to see that the O2 worked, what is the ECT reading?
What is the td?

Also I didn’t look at the ECT reading, I just looked to see that the 02 sensor said available/not completed instead of not available/not completed so there I just said it checked out.

I also did the compression test again on cylinder #4 and #3 with a cap of oil on the piston heads and on #4 it jumped from the original 90 to 100, and #3 went from the original, 90 just to about 93, and I’m almost positive I have no bent valves or anything bc I haven’t heard any funky noises from the engine and I checked the engine smoothness when I did timing and everything was smooth as butter, so I don’t think I have bent valves just on that info.

So that tracks me down to head gasket along with the fiav gasket. I’m gonna pull the head apart whenever I get the extra money for the head gasket kit, I’ll inspect the internals on the head then along with cleaning the piston heads and looking in the cylinder walls for scaring and put a new timing belt, pulleys and tensioner while I’m at it, I have new cam pulleys that I’m also going to put on. I’m gonna pull apart the tb and look for buildup and clean where is necessary.

I also have a hole in my radiator that I just put some jb weld over the hole just for now, but I’ll get a new radiator here soon as well.

It’s gonna be a bit but I’m gonna take a weekend to pull apart the head and do the gasket and clean everything and put it back together and hopefully after that, I’ll have a good running, sounding car.
 
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So I’m trying to find a tensioner and pulley for my eclipse and I’m not sure where the best place to look for one is, I found a couple online but I’m just unsure if the other brands will give me the same results that I need or what.

Where’s the best place to get a head gasket?

Found a cometic head gasket on stm tuned and there’s different bore sizes along with thickness and I’m not sure what to get.

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If your engine has never been touched before go with oem standard bore.
That’s what I was thinking but I thought the standard bore was 85mm and the only ones I can find that are 85mm are graphite ones and I’d rather not put a graphite head gasket in my car, so I was looking at cometic ones but I can only find it in 85.5mm at .056 so I’m not so sure what to do, also that was on stm tuned but I haven’t looked on eBay yet but i will if I have to I just wanted some input.

You need to do a leak down test to determine the cause of low compression first. Or at least a wet compression test to verify it’s not rings.
I did the wet test on it last week and the compression raised by about 2psi on the two low cylinders, I didn’t do #1 and #2 bc they were reading at 120 for #2 and 150 for #1 so then that made my assumption it’s blown in between cylinders 3 and 4 if I had to guess.
 
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