Engine issues?

[Wills7MGTE]

Ok last week my cars been down, it was running like crap and pouring black smoke, I suspected a vac leak, after 4 tear downs and reconnections no fix in sight I moved on and changed out the plugs, they were fouled and when I replaced the idle got better but was still surging between 400 and 1300 RPM's, so a buddy of mine said it could be a problem with the MAF, well 4 days later I got my MAF, which was yesterday, I installed it and jump started the car since the battery had drained, started up and idleed much better but still not perfect, idles surges between 500 and 750 and pours black smoke at idle and even more so when we revved to check the turbo and BOV. I know it could still be a boost or vac leak but I have hardpipes and a spearco replica FMIC from driftmotion, I've replaced almost all the hoses and I'm not finding any loose connections etc, the BOV seems to be working properly (its an HKS SSQV) so we ordered an o2 sensor tonight, it should be in tomorrow or worst case tuesday due to veterans day on monday. I'm just thinking of all the possibilities it could be hopefully the o2 sensor fixes it, I mean it makes since to my simple mind that when we replaced the MAF it got much better than it was but still doing the same thing so I know basically the O2 is like the back half of what the MAF does sort of so IDK my buddy and my dad kinda leaning towards it and for 30 bucks its not a expensive fix, hopefully it helps, my engine lights not coming on, I haven't tried jumping for codes yet but if the O2 doesn't work I may try that.

Any ideas other than vac/boost leak and O2?

 

[OneJoeZee]

Did you bother to check for codes yet?

 

[jetjock]

^ What he said. Unfortunately the O2 sensor isn't going to fix it because a bad one can't cause that kind of problem.

 

[Kckazdude]

Need to be looking at the injectors more than an O2 sensor. As JJ has already pointed out, it wont cause you to run as rich as you are.

 

[Wills7MGTE]

I haven't had a lot of time to do much with it, I work a lot, and when I do work on it it takes forever to get anything done with it, 7M is just poorly layed out in terms of lines and hoses and all the junk that must be removed to get to anything. Can you give me anything more specifiic than look at the fuel injectors? I can look at them all day long and not learn a damn thing so that statement is highly unhelpful.

I'll run for codes when I can but i work all night and part of tomorrow then go back in tomorrow night and since I pull 12 hours in a job you cant fall asleep at I don't see having time this weekend, I'm just sick of this POS 7M and am not in the position to do much with it so IDK what to do, I need the POS running but I really don't wanna pull the whole freaking thing apart and replace half of it just to fix this issue, which may or may not be minor.

If it's not a leak in the IC system then what other, maybe hard to get to vac lines are there to check, I have checked the PCV system, the only thing I found was the coupler TB to 3000 pipe has a small crack but it should seal as it isn't deep enough to expose the system, it just runs on the hard section and isn't close enough to the gap.

o2 sensor may not fix it but It's already ordered and won't hurt any to replace, the plugs I pulled were rich but that could be from the bad MAF couldn't it, it always ran much richer than a lot of mk3's I've found. Not trying to be a dick but "Look at your injectors" is a vague statement to someone who isn't a ASE Mechanic and hasn't fiddled with fuel systems at all. That and all the BS going into taking off the fuel rail I need more to go on than that.

Thanks

 

[OneJoeZee]

It takes all of 30 seconds to check codes.

 

[cuel]

Check with your local NAPA. There is usually one around that can test and clean injectors. Takes maybe 30 min.'s to get them out.

 

[Wills7MGTE]

Well joe when you work an hour from home and your car is at someone elses residence cuz it broke down there instead of at home then I'd say it's a bit of a pain to get it done when you work 12 hours drive an hour each way and sleep for 8 to 10 depending on how busy you get at work. Just don't post joe if you're going to be an ass about stuff, seriously.

Anyway, nobody here brought this up, but a friend in town with an mk4 believe it or not sugested it may be the TPS sensor, anyone know if this is a possibility that maybe we haven't considered yet? If it is how much does a TPS normally run? and how hard is it to swap out IIRC it's on the TB itself isn't it?

Anyway thats all the farther I have come on the car, If I am not wiped in the morning when I get off I'll maybe go run the codes. Anyway I'm loaded with possible issues, injectors (I still don't understand what would have failed and why they would fail in conjuction with the MAF having failed), TPS, changing o2 just cuz I already ordered it and it is old anyway, already changed out MAF with brand new one and checked all the boost/vac connections and lines.

Any more elaboration or ideas? and more on this TPS as a possiblility would be helpful.

 

[OneJoeZee]

Well joe when you work an hour from home and your car is at someone elses residence cuz it broke down there instead of at home then I'd say it's a bit of a pain to get it done when you work 12 hours drive an hour each way and sleep for 8 to 10 depending on how busy you get at work. Just don't post joe if you're going to be an ass about stuff, seriously.

I'm trying to help you and you get all butthurt. I wasn't even trying to make a smartass comment.

You're talking about 02 sensors, MAFs, TPS and shit, taking stabs in the dark about what's wrong when the first thing you should have done was pull codes so your car can possibly tell you what's wrong.

Why are you telling me how busy your schedule is? You had time to pull the plugs, change them, try another MAF, PCV and all that other stuff(alot of which wouldn't even cause your symptoms) but not 30 seconds to spare to put a paper clip in your diagnostic block and see if any codes came up?

The diagnostic block and codes are there for a reason... So you don't have to go on a goose hunt to find out what's wrong with your car, like you're doing right now.

 

[Wills7MGTE]

I fixed the PCV because it was leaking oil into the spark plug galley and caused some of the fouling issues on the plugs, I had 10k on the plugs and they were dark black and some had oil on them. The MAF was replaced due to it being part of the problem, since after putting the new one on the surging and rough idle went from terrible to being rough (Idled between 400rpm's and 1400rpm's also tried to die before MAF swap, after it now runs between 500 or so and 750 to 800 rpm's) so obviously by these results the MAF had something to do with the problem, a few weeks before all this I had a coolant line from the thermostat to the turbo leak all over the turbo side of the engine bay and it coated the MAF and filter so that may have had something to do with the MAF taking a dump.

I ask about the TPS because I know it can cause Idle issues from a friend who knows a lot about supras and is a member here (JMCBOOST). Yeah maybe a week ago I should have checked for codes, but I was fairly confident it was the MAF and maybe a boost/vac leak, after replacing several hoses and hunting for leaks for almost 4 hours I thought we had it whacked, since then I have not had time to dick with it, comes with working wierd hours on a demanding schedule. I'm on here now because I have time to get on here at work, being a dispatcher has it's perks sometimes.

I realize that codes will help, assuming it throws any which makes me wonder why the engine light has not come on if it has thrown codes? but there is such a thing as diagnosing and I have eliminated a few issues possible, so maybe someone could share about my TPS ? or any other things beyond injectors, frankly I don't think its the injectors, its easy to put forth a suggestion that costs a lot and is a pain and is also not that common and then stand by it with check codes before we attempt to help.

It may be injector related, I don't believe it is because of what I have seen it do, injectors would not work better with a new MAF, they would continue to be as shitty as before, and the odds of both failing at once are slim. Now things like a bad MAF or a bad TPS or a vac/boost leak are very common and cause issues like this, this issue is not a one fix solution, I think the MAF was a part if not half the problem as it helped quite a bit, so theres one piece of this puzzle missing.

I'm not trying to argue, I'm looking for answers, so vague ideas on what to fix and statements about me not checking codes don't help, it's over we are beyond it I will check for codes when I get to the car either tonight or maybe sunday until then I need to find out what I can about what may be going on here, I appreciate IJ's chim in and I know 02's don't cause rough idle but I'm going off info from a fellow supra owner who I think knows his shit, if he doesn't ill find out soon enough, but IJ's statement doesn't help without some explanation, I'm not pulling the intake manifold off and putting several hours labor and my own cash into a wild goose chase and then find out it was a TPS sensor gone bad or a boost leak, you understand my point?

Anyways any theories or help is appreciated, as long as you explain what you mean so I can understand what your pointing to, before code throwing was popular diagnosing came from educated guesses on what the car was or wasn't doing, so lets try that till I get those codes checked.

 

[OneJoeZee]

The check engine light does not have to be on for codes to be stored.

 

[Wills7MGTE]

Ok was wondering on that since a buddy has his come one anytime there are codes, even for the Boost leak code and one for the cooling system he said popped up in SC.

 

[Kckazdude]

Black smoke and fouled plugs indicate your running rich. Vacuum and boost leaks will make you run lean. You need to find out why your injectors are letting too much fuel in. It could be a faulty TPS. It could be an injector getting a false signal and staying open. It could be an injector that has a stuck needle. It could be a faulty temp sensor. It could be a short in the wire harness somewhere. It could be an open in the harness somewhere.

The point is there are a lot of possabilities going on right now. Being that your car is at least 170 miles away from me, I cant tell you what is wrong with it. That is precise as I, or anyone else with any expirience, can get without more information or being with your car. Your the one near the car. Your the one with the problem. Diagnose it a little and give us some information.

Better yet get mad at all of us. Replace everything that dont need replaciong. Waste plenty of money on parts you dont need. Then come whine about on a forum board. In the meantime, I am gonna go drive my Supra that runs just fine.

 

[IJ.]

Will just pull the codes.....

 

[supraguy@aol]

Don't know if it's possible on the Supra, but I once had the cold start injector go bad/ stuck open in my Z car, and I could barely keep it running due to all the fuel pouring in, and all the black soot pouring out.

 

[Wills7MGTE]

The point is there are a lot of possabilities going on right now. Being that your car is at least 170 miles away from me, I cant tell you what is wrong with it. That is precise as I, or anyone else with any expirience, can get without more information or being with your car. Your the one near the car. Your the one with the problem. Diagnose it a little and give us some information.

Better yet get mad at all of us. Replace everything that dont need replaciong. Waste plenty of money on parts you dont need. Then come whine about on a forum board. In the meantime, I am gonna go drive my Supra that runs just fine.

Well this was very uneccessary, it's not wasting money when its helping solve the problem I can't state this any more than I have the MAF and the other small repairs did help the problem but not eliminate it. I'm glad your 170 miles or more away, too bad it's not farther, I don't normally wish bad on people but I will have to admit the day your's causes you grief and you have trouble finding a problem I will enjoy it, I've given plenty of info if you'd actually attempt to digest any of it thats another issue.

I appreciate the people who have tried helping, and hopefully it won't take much longer, It's a shame people on this forum can be so rude and negative and unhelpful about things, if you wanna bitch about how someone is doing something then fine do it to yourself or in your own thread, the above poster was new maybe I don't know, I know some good guys in TN but they don't act like dicks anytime someone asks for info

I'm planning to check for codes but I'm thinking it could be the TPS as mine is original and they are common for failure on our cars as I've seen using the lovely search feature here. I apologize for snapping at Joe, at least he's attempting to help, kickass mk3 owners isn't so kickass when it comes to being a decent human being, I've helped people out on here who should have approached thier idea or issue in a different way in my opinion but I never bitched and bashed them for how they worked on thier car like you did buddy, it's a shame SM has degraded to this kind of behavior as accepted, people say things out of context but you're just plain rude.

Anyway, anyone with any other input please do so and I'll post if I find any codes when I check, may be sunday afternoon or late tonight before I can though due to work.

 

[Wills7MGTE]

I hadn't thought of the cold start injector, long shot but it may be the case, codes may tell me for sure, sadly OBD1 and our diagnosing setup is pretty primitive.

 

[2543arvin]

Okay, I think the point that everyone is trying to make is that it only takes 15-30 seconds to pull the codes, and any post that you will make on a forum takes longer than that. I know that with the limited amount of funds that I have I cannot afford to replace anything that may or may not fix my problem. The TPS is not an inexpensive part by any means, so before assuming that is cavaet, I would pull the codes, because it will verify whether or not the TPS is bad or needs adjustment.

 

[Kckazdude]

I have read the thread. All of it actually. I even read through your snapping at Joe, which prompted some of my reply.

Here is what I have gathered from reading through this.
1) your car is in a bad state of tune. From the description it is running rich.
2) you have thrown parts at it and ordered more without diagnosing the problem first.
3)you work a lot of hours, as most of us do. (I work 65-75 hours a week)
4)you live a decent distant from work.
5)you snap at people that dont give you the answers you want.

If you would provide us with more information then we could give you more specific things to check to resolve your problem and have you driving and enjoying your car. I would rather hear of you enjoying your car than repairing it. I have had my share of repairing my car until 3AM so I could be at work at 7.

If you are intersted in learning how to diagnose and repair your car then I will help you all I can. The more you diagnose the easier and faster it becomes.

 

[jetjock]

The way I see it you have three issues:

1) Lack of knowledge about how the car works. Because of that you've no idea how to diagnose it correctly.

2) Friends who're the same regardless of what they think they know.

3) A serious attitude problem.

I'll leave you with three pieces of wisdom:

1) Read the service manual.

3) It's unlikely to be your TPS.

3) In life there is no such thing as not enough time. There are only priorities you decide.