Low idle and running rich

Mitshiko · 01-13-2008, 04:40 AM

Ok so...I JUST took my car out tonite. Its an 86.5 7MGE engine, and it was seemingly not as powerful as it should. I assumed it was from my BHG. I just got it for 500 dollars, and I knew it had a blown head. I went to test it out, after getting the car in my name, and insured, that I should test it a bit more. I took my girlfriend home, and it was running ok. when I got back home, I went to check email, do whatever, and went to go to my aunts just a few blocks down. and...it kept dying. The engine wont hold RPM unless I rev it high, and then kinda...its not knocking, but its clunking. I hear a hissing from the back of the engine. I called the previous owner, and he told me that, Yes, he heard it too, and he and his buddy both couldnt figure it out. I have this hose, kinda "S" shaped, that I found sitting between the radiator, and frame under the hood. it has a little clamp on the end, so i know it goes somewhere. I also know with the BHG i had in my 89, that didnt affect the idle all that much, at least not enough to kill it. there is just coolant going out the exhaust chamber at times, and its not even a serious leak.

I know that when I ran seafoam through my 89, i had to pull off a vaccum line, and pour it in, which made the engine do the same thing, and make the same hissing noise.

What I would like to know, and hopefully fix, is where the hose goes, or whats loose. I cant see anything, but its also dark out, and I am not sure what is hissing, or sucking...

I read on another forum, (Supramania) that something like what im going through happened because of a vaccum leak, and something called the ISC. Im sorry to say I dont know what that is, and any help would be awesome. Pictures would help too...

Irish_Mechanic · 01-13-2008, 08:48 PM

ISC should stand for Idle Speed Control. Theres a good chance it IS a vaccuum leak, mainly because you said it runs okay at W.ide O.pen T.hrottle, which in most cars has its own preset fuel mixture. if it IS running rich, you probably DONT have a vaccuum leak, because that would cause a LEAN condition (too much air as compared with fuel). check the connnections at your air meter, which i've seen people refer to as an AFM on supras (all the other cars i've owned and worked on called them MAF's and MAP's...). If that sensor is bad(or has a bad connection), theres a good chance that its going into 'limp' mode and is dumping a generic amount of fuel because it's not getting an air reading. let me know what you find...good luck

SleepysSupra · 01-13-2008, 11:37 PM

Well if the blown head gasket is filling the cylinders with antifreeze that could cause it to stall out too. I just did the head gasket on my 88 7MGTE and it wasn't hissing, thats more likely a vaccume leak, but if the car sat for a while the antifreeze would seep into the oil pan and it would run fine for a while but after running for a while it would start runnning rough and then die out. At ope throttle it would run fine because the engine was exhausting the antifreeze faster than it was drawn in. If your leak isn't a very big leak then that could very well be the case. Mine on the other hand, I put a new head gasket on mine and never had the head checked. My mistake, I had to do it twice and have the head machine at a local shop here because after checking my head I foud it was warped. The machine shop had to take two thousanths of an inch off mine to fix it. Well let me know what you find.

Mitshiko · 01-14-2008, 04:14 AM

Thats probably the case. the guy said it had a blown head, and it seems to act like it. Its fine when the engine is cold, and then after warming up, it starts to die out, and is hard to get up to speed. it kinda goes in and out of accelerating and stuttering, like its trying to die.

a while ago it was idling really rough, kinda clunking a bit and idling at 500-600, and would rev like....slow...going WOT when its just warming up, like...5 minutes after driving seems to have no affect on the power or speed.

Anyways...I found a link to buying a HG set... 7MGE Toyota Head Gasket Set (86-93) from PartsDinosaur.com..I know its cheap, but please understand, I cannot afford to do everything right now. The jackass I bought my 89 from hid every last thing from me until after the engine was running and was able to stretch its legs. At that time, that "Stop Leak" crap he put in there blew through the head, the crap in the heater core was forced out, and massive amount of coolant went into the engine and that cost 1200 bucks. plus the set was like single gasket was just for the top and I was charged 150 for that. I got new struts and that was about 540. new tires was about 520. I had about 5500 dollars to make this work, but insurance hit hard, so now im down to my last reserves of 100 bucks. I just got this 86 for 500 bucks, and it needs some minor things it seems like. at least minor compared to what went into the other one.

Anyone know how to take struts off the car...lol, kinda thinking on selling it, and salvaging what I can...lol

Mitshiko · 01-14-2008, 04:16 AM

Quote:

Originally Posted by Irish_Mechanic

f it IS running rich, you probably DONT have a vaccuum leak, because that would cause a LEAN condition (too much air as compared with fuel). check the connnections at your air meter, which i've seen people refer to as an AFM on supras

What i meant by rich was that when I started it up, smelling the exhaust was almost like stucking a gas can to your nose and inhaling...

mkiiisupra · 01-14-2008, 04:27 AM

So now we know the truth of the situation, You were huffing gasoline and was so far gone that you imagined the whole situation....

Mitshiko · 01-14-2008, 04:33 AM

Quote:

Originally Posted by mkiiisupra

So now we know the truth of the situation, You were huffing gasoline and was so far gone that you imagined the whole situation....

Dude....srsly plx...Im in need of help, not jokes...

If you have any ideas that arnt listed there, please let me know

mkiiisupra · 01-14-2008, 04:44 AM

sorry thought it was funny lol, if there was any info i could offer you i would

Irish_Mechanic · 01-14-2008, 04:57 AM

Quote:

Originally Posted by Mitshiko

What i meant by rich was that when I started it up, smelling the exhaust was almost like stucking a gas can to your nose and inhaling...

hmmmmmm........ did you say that the exhaust had backfired too?

Mitshiko · 01-14-2008, 09:06 AM

No, it never backfired. It just began idling extremely rough, and clunking as it ran. Weird thing is i disconnected the ISC started it, it idled better, small amount of clunking, but at least it wasnt dying. Later on, I put the connector back on and it kept running ok.

It seems that when its warmed up, the engine just cant live, i would assume this is due to the BHG, but I also believe I have a vaccuum leak based on what others are saying, or a hose is borked somewhere, or not connected to the right place. I will hopefully getting it to a trusted mechanic soon...thanks all for your help...sorry i am such a bother.. >_<

01-13-2008, 04:40 AM	#1
Mitshiko Stock Join Date: Jan 2008 Location: Portland, OR Posts: 11	Low idle and running rich Ok so...I JUST took my car out tonite. Its an 86.5 7MGE engine, and it was seemingly not as powerful as it should. I assumed it was from my BHG. I just got it for 500 dollars, and I knew it had a blown head. I went to test it out, after getting the car in my name, and insured, that I should test it a bit more. I took my girlfriend home, and it was running ok. when I got back home, I went to check email, do whatever, and went to go to my aunts just a few blocks down. and...it kept dying. The engine wont hold RPM unless I rev it high, and then kinda...its not knocking, but its clunking. I hear a hissing from the back of the engine. I called the previous owner, and he told me that, Yes, he heard it too, and he and his buddy both couldnt figure it out. I have this hose, kinda "S" shaped, that I found sitting between the radiator, and frame under the hood. it has a little clamp on the end, so i know it goes somewhere. I also know with the BHG i had in my 89, that didnt affect the idle all that much, at least not enough to kill it. there is just coolant going out the exhaust chamber at times, and its not even a serious leak. I know that when I ran seafoam through my 89, i had to pull off a vaccum line, and pour it in, which made the engine do the same thing, and make the same hissing noise. What I would like to know, and hopefully fix, is where the hose goes, or whats loose. I cant see anything, but its also dark out, and I am not sure what is hissing, or sucking... I read on another forum, (Supramania) that something like what im going through happened because of a vaccum leak, and something called the ISC. Im sorry to say I dont know what that is, and any help would be awesome. Pictures would help too... __________________ 86.5 Mk3 N/A W58 89 Mk3 N/A auto (Selling...)

01-14-2008, 04:14 AM	#4
Mitshiko Stock Join Date: Jan 2008 Location: Portland, OR Posts: 11	Thats probably the case. the guy said it had a blown head, and it seems to act like it. Its fine when the engine is cold, and then after warming up, it starts to die out, and is hard to get up to speed. it kinda goes in and out of accelerating and stuttering, like its trying to die. a while ago it was idling really rough, kinda clunking a bit and idling at 500-600, and would rev like....slow...going WOT when its just warming up, like...5 minutes after driving seems to have no affect on the power or speed. Anyways...I found a link to buying a HG set... 7MGE Toyota Head Gasket Set (86-93) from PartsDinosaur.com..I know its cheap, but please understand, I cannot afford to do everything right now. The jackass I bought my 89 from hid every last thing from me until after the engine was running and was able to stretch its legs. At that time, that "Stop Leak" crap he put in there blew through the head, the crap in the heater core was forced out, and massive amount of coolant went into the engine and that cost 1200 bucks. plus the set was like single gasket was just for the top and I was charged 150 for that. I got new struts and that was about 540. new tires was about 520. I had about 5500 dollars to make this work, but insurance hit hard, so now im down to my last reserves of 100 bucks. I just got this 86 for 500 bucks, and it needs some minor things it seems like. at least minor compared to what went into the other one. Anyone know how to take struts off the car...lol, kinda thinking on selling it, and salvaging what I can...lol __________________ 86.5 Mk3 N/A W58 89 Mk3 N/A auto (Selling...)

01-14-2008, 04:27 AM	#6
mkiiisupra Lexus & 550's Join Date: Sep 2007 Location: Las Vegas, NV Posts: 570 Blog Entries: 1	So now we know the truth of the situation, You were huffing gasoline and was so far gone that you imagined the whole situation.... __________________ 1990 Toyota Supra Turbo A/T ------------------------------------------------ Questions about oil? take a look http://www.supramania.com/aehaas/

01-14-2008, 04:44 AM	#8
mkiiisupra Lexus & 550's Join Date: Sep 2007 Location: Las Vegas, NV Posts: 570 Blog Entries: 1	sorry thought it was funny lol, if there was any info i could offer you i would __________________ 1990 Toyota Supra Turbo A/T ------------------------------------------------ Questions about oil? take a look http://www.supramania.com/aehaas/

01-14-2008, 09:06 AM	#10
Mitshiko Stock Join Date: Jan 2008 Location: Portland, OR Posts: 11	No, it never backfired. It just began idling extremely rough, and clunking as it ran. Weird thing is i disconnected the ISC started it, it idled better, small amount of clunking, but at least it wasnt dying. Later on, I put the connector back on and it kept running ok. It seems that when its warmed up, the engine just cant live, i would assume this is due to the BHG, but I also believe I have a vaccuum leak based on what others are saying, or a hose is borked somewhere, or not connected to the right place. I will hopefully getting it to a trusted mechanic soon...thanks all for your help...sorry i am such a bother.. >_< __________________ 86.5 Mk3 N/A W58 89 Mk3 N/A auto (Selling...)

01-13-2008, 08:48 PM	#2
Irish_Mechanic Intake Join Date: Jan 2008 Location: Lancaster PA Posts: 45	ISC should stand for Idle Speed Control. Theres a good chance it IS a vaccuum leak, mainly because you said it runs okay at W.ide O.pen T.hrottle, which in most cars has its own preset fuel mixture. if it IS running rich, you probably DONT have a vaccuum leak, because that would cause a LEAN condition (too much air as compared with fuel). check the connnections at your air meter, which i've seen people refer to as an AFM on supras (all the other cars i've owned and worked on called them MAF's and MAP's...). If that sensor is bad(or has a bad connection), theres a good chance that its going into 'limp' mode and is dumping a generic amount of fuel because it's not getting an air reading. let me know what you find...good luck

01-13-2008, 11:37 PM	#3
SleepysSupra Stock Join Date: Dec 2007 Location: Meriden, Connecticut, USA Posts: 16	Well if the blown head gasket is filling the cylinders with antifreeze that could cause it to stall out too. I just did the head gasket on my 88 7MGTE and it wasn't hissing, thats more likely a vaccume leak, but if the car sat for a while the antifreeze would seep into the oil pan and it would run fine for a while but after running for a while it would start runnning rough and then die out. At ope throttle it would run fine because the engine was exhausting the antifreeze faster than it was drawn in. If your leak isn't a very big leak then that could very well be the case. Mine on the other hand, I put a new head gasket on mine and never had the head checked. My mistake, I had to do it twice and have the head machine at a local shop here because after checking my head I foud it was warped. The machine shop had to take two thousanths of an inch off mine to fix it. Well let me know what you find.

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