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Going back to the idle issue...
Have you set the TPS to .54 volts/
Have you check the IAC (Idle Air Control Valve) under the throttle body and perhaps removed the piece it screws into under the TB. If you have not removed it, then be sure to soak....repeat SOAK the little bolts with PB Blaster or other release so you don't break them off. Clean all the passages in this piece of any carbon build up. The IAC valve controls the air going into the TB at idle as the little pental opens and closes to allow air into the TB.
hi John, I have pulled the throttlebody and cleaned all the passageways as you suggest, and I have done the minimum idle adjustment a couple of times.
I am still waiting for the scanner to see what the IAC counties as aklim has suggested. that should be the verification I need to see that air is getting in somewhere if the throttlebody is closed and the IAC count is zero.
however I think I may have found the culprit, I have previously smoked this engine but I decided to try again now that I have seen this coolant pooling in the valley by the bolts heads.
I blew into the brake booster vacuum hose with cigar smoke, I started to get smoke tendrils coming out from Wright, where the coolant was pooling.
perhaps I have a leak that is both letting coolant out when I turn the engine off, sucking air in when the engine is on, and also sucking coolant in when the engine is on.
I have never seen a intake gasket before, but I assume it keeps the air from the intake separate from the coolant in the engine below? Is it possible that I can have a compromised gasket that meets the conditions above? Letting air in, being the source of a vacuum leak, and also letting cooling out when the vehicle cools off, and thirdly because the exhaust in this car burns my eyes , Is it possible that coolant is being sucked in the intake along with the extra air and then getting burned creating the funky smell which is burning my eyes? And leaving my clothes very smelly after driving a vehicle.
tonight I will Google what the intake manifold gasket looks like and I can probably answer my own question but in meantime I just asked Google and here's what I got so it looks like I can have an intake gasket leak that allows both air into the intake and coolant into the intake and then cool and out of the leaking spot after the engine is cooling down or cooled off. note that I do not have any trouble codes. (apologies in advance for what looks like grade 3 grammar, I use Siri on my iPhone to dictate to save me a heap of time and sometimes her grammar bites me in the butt, it is still however worth the hours and hours of typing that it saves me!)
Originally Posted by John A. Marker
Going back to the idle issue...
Have you set the TPS to .54 volts/
Have you check the IAC (Idle Air Control Valve) under the throttle body and perhaps removed the piece it screws into under the TB. If you have not removed it, then be sure to soak....repeat SOAK the little bolts with PB Blaster or other release so you don't break them off. Clean all the passages in this piece of any carbon build up. The IAC valve controls the air going into the TB at idle as the little pental opens and closes to allow air into the TB.
Last edited by VikingTrad3r; 11-06-2015 at 02:39 PM.
you know, this 85 has 44k miles on it, runs strong. blows my 87 out of the water (though, now i wonder if it has been running lean!) and i cannot beleive how many seals were toasted.
The two smaller rectangular openings at each end of the gasket are for coolant to flow from one side of the heads to the other side. The four larger openings are the air passages from the intake to the heads. Usually you find the gaskets compromised at the lower part of the gasket at the valley for the air not coolant and this results in oil being sucked out of the valley and into the head and burned...fouling the plugs. Most often this is #7 or #8 cylinder. The smoke coming out where you indicated would show that the gasket is compromised. Time to replace it and that will probably solve your idle issue and the coolant issue.
I usually wipe a very thin layer of the right stuff onto both sides of the gasket around the coolant passages. I have personally not had a intake gasket leak coolant. Get a gasket set that has all the gaskets including the runners and plenum gaskets. Throw out any end seal gaskets and use The Right Stuff or 100% Silicone. You have to let the Silicone sit 24 hours before using. The Right Stuff can be used immediately.
Label all your bolts as you remove them. There are some that are different lengths that hold the runners to the intake. Note that there are a couple of bolts in between the two runners UNDER the plenum when you remove the plenum. You do not have to remove the fuel rails or injectors. But you will have to disconnect the fuel lines at the front of the engine. Be sure that you have rubber push on end caps to put on the fuel lines at the front of the engine. You will have fuel from the tank leak if you don't cap them off. Be sure to label all electrical wires and vacuum lines. You will be thankful when you got to put things back together. As a bit of advice...I usually pull the plug on #1 and turn the engine by hand until compression is felt in cylinder #1 and then line up the timing marks. This makes it a little easier when you pull and then re-install the distributor.
If you have time and the tools, gasket match the intake, runners and plenum. Doesn't take long and is fairly easy.
Last edited by John A. Marker; 11-06-2015 at 03:37 PM.
Thanks guys, your comments are a great help to me! never done this.
They have a set at my local parts store, including the runners top and bottom, for 50$. anything special i should look for in the intake manifold gaskets exclusive the the 85? also i have the oring kit for all injectors as well.
also i plan on following these vids for a rough idea, i have the 87 shop manual so im sure its more or less the same.
Forget the first video, the second is more valuable on putting things back together. There is a big difference between the LT1 and the L98 (your 85). You have to drain the radiator, remover the plenum, runners, disconnect the fuel lines, pull the distributor and pull the intake. The bolts to the runners to the intake are a PITA to get to and are TORX.
I would leave the fuel rail in place unless for some reason you want to remove it and the injectors. You don't have to remove it to get the intake off. You can leave it on the intake. One less thing to mess with.
I had the same problem many years ago with coolant pooling on the intake with my 85. the plug in the nearby cylinder had a white tip and I had white smoke at start up. so the coolant was getting in there. I did the manifold gasket replacement project (not fun) and those problems have been gone for about 10 years.
next, you drop in fuel pressure is most likely related to your dampner. it will rupture over time. easy fix with a piece of fuel line.
last, I have no idea on the idle. I have had the same nonsense for years and have not had the time to even start investigating. I am betting on three things.. o2 sensor, dirty iac or just bumping my min idle speed - doing the min throttle adj. I have checked for vac leaks and have found nothing.
edit, i am abviously not doing this pressure test right. that or my 87 has a pressure leak as well. i have tried this on both my 85 and 87 and i cannot get the pressure gauge to register any pressure. when i push IN on the stroke, it reads pressure but i can't get it over 7 psi.
when i release, the pressure goes back to zero.
ok guys i rented the local shops coolant pressure tester and i cannot get it to pressure up at all no matter how fast i pump.
i have looked around the car for pooling radiator fluid and i cannot see any anywhere.
we are suspecting a leaking intake gasket for sure as i got some smoke tendrils out of that area on the driver side, same as where the coolant was pooling.
however, i was wondering if there is further testing to determine if i have a cracked head gasket or a cracked block?
i have no oil in my coolant, and no coolant in my oil.
but, my rad fluid is extremely rusty colored!
Its an 85, so i think i have iron heads, and iron block right? that could mean the rustyness is coming from where the intake meets the heads?
anyway, are there any further tests i can do to determine if i have blown head gasket or a cracked block?
your going to see a compression tester arn't you.
Last edited by VikingTrad3r; 11-07-2015 at 03:09 PM.
back to the pressure testing... I had a buddy come over and put his hand on the return line into the top of the radiator and he could feel the pressure pulsing in it but on the return stroke of the tester pump it would allow the pressure to alleviate almost like there's a check valve that's broken inside this pump. I left the gauge attached to the car and started the engine and the pressure went up to 13 PSI. Turn the car off and it has been slowly bleeding off over the last 25 minutes.
I would've thought if I had a leak, enough to make the exhaust white, cause the smell, and put green residue on my tailpipe tips that the pressure would bleed off faster than that?
any thoughts would be appreciated. I am on my way to return the coolant pressure tester and bring home the compression tester for the cylinders I would like to know if I'm dealing with a head gasket or a cracked block versus an intake gasket I suppose it could be both
Originally Posted by VikingTrad3r
ok. i took a white rag and dabbed it on both tailpipes where the condensation was building up. GREEN!
dun dun DUUUNNNN.
Last edited by VikingTrad3r; 11-07-2015 at 05:38 PM.
Pull plugs #7 and #8 and check them. Are they exceptionally clean....like new? That would indicate coolant is getting into the cylinder. So that could indicate a blown head gasket. Or somehow the coolant is leaking from the intake and getting sucked into the intake port into the cylinder.
Pull plugs #7 and #8 and check them. Are they exceptionally clean....like new? That would indicate coolant is getting into the cylinder. So that could indicate a blown head gasket. Or somehow the coolant is leaking from the intake and getting sucked into the intake port into the cylinder.
Enough coolant to be thrown out of the cylinder but not enough to hydrolock? That guy must have some good luck.
aklim........he could have a blown head gasket that has not gone too far and is just spraying coolant into the cylinder. Pressure is talking a long time to drop so it could still be in the "just happened stage".
Enough coolant to be thrown out of the cylinder but not enough to hydrolock? That guy must have some good luck.
Well Ak I am a very lucky guy. !
But seriously, i have zero water in my oil. And the coolant i found was in too of the intake in the little valleys under the plenum. and the threads were a bit base of the hex head bolt, where it sits flush on the intake head has a bit of rust on it....im guessing its an intake gasket leak and not a head gasket/to block leak.
but the compression test should give me the confidence. im a total noob at alllll this stuff, first time turning a wrench was a year ago, so the more affirmations on the theory the better.
today i flushed the coolant. it took over an hour to stop the rust. ran the garden hose into the knock sensor. i avoided removing the thermostat by running the car for a while to open it, then drained it while filling at the top. did this 6 times and finally in the last time water was fairly clear. drained, then filled with vinegar. will be draining in 30min. then flushing with water again. will do compression test tomorrow to see if we are talking head gasket or intake gasket as i suspect. the reason i suspect this is i do not have any issues with my oil being contaminated.
11-06-2015, 02:02 PM
Idle
...he could have a blown head gasket that has not gone too far and is just spraying coolant into the cylinder. Pressure is talking a long time to drop so it could still be in the "just happened stage".