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92 9kt will not stay running / will not boost HELP

1K views 29 replies 6 participants last post by  UK9K 
#1 ·
Alright well I've put this off long enough with hope that the car would fix its self while I wasn't looking. This hasn't been the case however so I'll tell the story and hope for suggestions.

About a week ago I decided to take my 1992 Turbo 9000 out for a drive after I had let it sit for a week because it has an expired inspection sticker. I started the car up and drove it till it was warm. I then went to down shift to experience some of that lovely boost I had been missing after driving my '96 Ford Probe GT:roll: for a week. The car boosted right to the middle of red(normal) and I let off the gas and slowed down a bit. I let the car boost a couple of times but about the third time I tired to boost in 5th gear and it didn't even move the boost gauge into the orange it just bogged and gave that low pitch growl of an NA car in 5th. The 'battery' light then flicked on followed by the 'oil' light and then the 'check engine' light as I was pulling over. I shut the car off and my friend and I checked the fluids, everything seemed to be ok so I started it again. The car would not idle when I started it so I turned it back off. I called my other friend who took half an hour to arrive. after he got there I started the car which started fine and idled as it does normally so I began to drive it to my house that was only about 5 miles away. I started off and I noticed the car still did not want to boost. About half way there I noticed the check engine light again. When I stopped the car would not idle normal at all, shuddering and banging so i turned it off, drove home with my friends and waited a few hours. I came back later that night and started the car and headed home, the check engine light came on but I ignored it being so close to home. I parked it and have let it sit for about a week.

Tonight I figured I would try to figure out whats wrong. I cleaned out the 'APC' valve (not sure if that's what it's rally called, but the solenoid with three hoses going to it) I have had problems with this before and my car would hardly boost at all being in a limp type of mode. I also figured I would check on the waste gate thinking it might be stuck it moved a little but I got metal in my eye and cut my hand so I gave up on that. I attempted to start the car since I had cleaned out the 'APC' valve. The car started immediately displaying the 'Check engine' light it was sputtering then showed the 'TCS' and 'Break' light then shut off. I started it again and it just had the 'Check engine' I then turned the steering wheel and the car turned off. I started it again and revved it to about 3k so I could hear the turbo. The entire car just shook and the turbo sputtered awful.

It seems to me I have something wrong with the turbo?:confused:
If anyone actually takes the time to read this I would certainly love to have my car back I hate driving an Automatic Ford Probe.:(
 
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#2 ·
Am in the same boat s you mate. Got 92 9000 2.3t. Spluttering same as you, not boosting up. It also wouldn't hold idle too. That was sorted when the guy changed the O2 sensor. My car has been at the Saab specialist since Dec 19th, 2006. I have foned up every couple of days, to get a progress report, but alas, he is stumped at the mo why it won't boost up.
 
#3 ·
I know it might sound silly but check all the vacuum hoses, then check the hoses from the turbo to the intercooler and from the intercooler to the throttle body for splits etc. Also check the hoses onto the dump valve. Check the inlet manifold for blown out plugs.
 
#4 ·
Marrk said:
I know it might sound silly but check all the vacuum hoses, then check the hoses from the turbo to the intercooler and from the intercooler to the throttle body for splits etc. Also check the hoses onto the dump valve. Check the inlet manifold for blown out plugs.
No doesn't sound sillu I actualy happend to talk to a friend of mine who worked on a 9kt with the same problem he said it was the vacum lines, and that would make sences because I let it sit in the cold for a week while it was about 10 degrees. I am willing to bet thats my problem. I didn't think about checking for blown plugs I'll check that too.
Thanks for the reply.
 
#5 ·
UK9K said:
Am in the same boat s you mate. Got 92 9000 2.3t. Spluttering same as you, not boosting up. It also wouldn't hold idle too. That was sorted when the guy changed the O2 sensor. My car has been at the Saab specialist since Dec 19th, 2006. I have foned up every couple of days, to get a progress report, but alas, he is stumped at the mo why it won't boost up.
So changing the o2 sensor just fixed the idle but not the boost?
 
#6 ·
Promaine said:
So changing the o2 sensor just fixed the idle but not the boost?
This would not be surprising. The ECU uses feedback from the O2 sensor when cruising or idling, to maintain fuel economy (closed loop operation). Under full throttle, or above a certain throttle percentage, the O2 sensor signal is ignored and the ECU relies on the fuel maps alone. Even at part throttle, I'm reasonably certain that the ECU (whether APC or Trionic) does not consider O2 sensor information when controlling boost levels.
 
#7 ·
I put new plugs in and it seemed to help the idle some what but then after shutting it off and starting it again it began to chug and shake like it was missfireing. the entire time the engine light was still on.
The car is also making a noise my friend noticed it sounds like wet shoes on a tile floor.
I don't know but it just seems like what ever happend it had to be something that could just break instantly because thats what happend it went from fine to messed up not something gradual.
 
#9 · (Edited)
I was driving along a dual carriageway at about 75/80 mph, indicated to go into the inner lane to overtake a car, put my foot down, then blurggghh, the revs just dropped right down, speed fell to about 35/40. NO LIGHTS came on the dash tho. I quickly pulled back out into the outer lane. I had my foot near enough flat down, but the revs wouldn't go up, and the engine was just chugging along and about to die. This all happened all of a sudden too. No prior warning of any noises or lights at all. Did notice that the boost gauges were sitting at normal idle position, not dropping down or going up tho.

When the guy first had a go at my car, when he tried to start it up to drive it into the garage, it would start but just die straight away, so he had to push it in. He discovered that the new fuel pump was fitted with the feed and return pipes the wrong way round, so switched them around, got the car started, but was idling like a bag of poo.

Plugged it into the diagnostics, and had I think 5 faults. 1 saying the engine was running lean, and 1 saying the engine was running rich. So he changed the O2 sensor, that cleared those 2 faults, and it could idle a bit better, it did still chug a bit at idle, but was constantly dieing. Then he tried swapping the DI cassette, but made no difference, swapped the AFM, but made no difference either. He said he swapped over a couple of over stuff, and now it does idle steady, drives like an NA, but when he puts his foot down, it'll start to build up, but drop straight back down at 2psi. It won't go over 2psi. He has also changed my ECU and DI brain for standard ones, and reconnected the turbo hoses to the APC, which he also changed for one out of a working car, just so he could start with a ' factory standard ' car to get it all working as normal again.

He also changed my FORGE BOV with a normal standard one. He did not changed the FORGE actuator tho. I told him I had a 14-18 psi spring fitted inside the actuator, so theoretically, it SHOULD be giving a minimum of 14 psi, right? But nothing. Could the fact that the actuator turnbuckle has been turned in 3/4 turns be affecting the boost up? Could it be too tight for the standard ecu to handle or would it not make any difference? he did take the actuator off and opened it up to check the diaphragm was ok, which it was.

Problem now is no boost. He has checked all the hoses, which I had changed to silicone ones before, all are fine.
 
#11 ·
Yeah, he tried that one. I asked him to make sure, but only getting 2psi and then drop off. Is there anything he could have missed?

He's changed the;
ECU for standard
DI ECU for standard
Forge dump vlave for standard
Reconnected the turbo hoses to the APC
Changed the O2 sensor
No faults showing on diagnostics
Checked the FPR , is ok
Fuel pump is ok
All silicones turbo hoses are ok
Forge actuator diaphragm is ok, actuator rod is free moving, albeit tight
 
#13 ·
The intercooler has split? It can do that? So have I turned up the boost a tad too high then? Or reckon just a leaking/blown intercooler hose? I shall ask him to check those then. Is there any way to check if the intercooler has split without actually taking it out?
 
#14 ·
Not a proven method, but I'd do it. Take the dump valve off and feel the air changing with the revs, then take the delivery pipe hose off and put tape or something over it, to air seal it, now all the air will come through the DV hole, try revving the engine a little and covering the hole, if the intercooler is split hopefully blocking off these places will make the split audible as there'd be a lot of air coming out of it.
 
#15 ·
So pull the little hose that goes on the front of the dump valve off, leaving the nipple tube exposed, and put some tape over the end of the dump valve to seal it, and clamp closed the little hose with mole grips, right? And try rev the engine to listen for air leaks. Will mention it to the guy tomorrow, if he is in.
 
#16 ·
Darn, don't think I explained properly. I'm thinking this is just a crude way of pressure testing the hoses from turbo to throttle body (as Marrk suggests).

Basically you're trying to seal the delivery pipe to get the air to be audible from wherever it may be leaking for whatever reason. Take the DV off, no need to undo the vac hose, the DV won't be doing anything. Also take off the rubber hose from the throttle body and seal the end of the hose. From this point all the air will be coming out of the DV hole, then try revving a little to make sure the air from the hole changes speed/flow/pressure (etc). Then for short amounts of time (only a few seconds at a time), seal this hole aswell so the only orifis for the air to go to is the leak from the intercooler (or wherever).

Obviously the engine might not want to idle as the air is going directly from the atmosphere into the throttle body, and the IAT sensor will be giving relatively spurious readings to the ECU.
 
#20 ·
Ok, foned up matey and asked him if he had checked for any leaks from any of the vacuum hoses, including the intercooler in+out, and he says he did the check with the dump valve off before, but got no leaks to report.

He already checked the plugs before aswell, all four were fine, no cracks and only lightish beige coating. Now what?
 
#22 ·
If you've tried clamping off the wastegate hose as Marrk says and you're only getting 2psi, considering the engine's turning fine, which at 3k rpm it must be, then there's something wrong with the turbo, it's just plain not boosting, Small chance the pin on which the wastegate hinges has broken and the actual wastegate flap has dropped off come off, on the turbine side of the turbo that is. You'd need to take the downpipe off to check this theory.
 
#23 ·
I told him I had a 14-18 psi spring fitted inside the actuator, so theoretically, it SHOULD be giving a minimum of 14 psi, right?

No not really, thats a really strong actuator spring, you typically want a 5 to 10psi spring to get the correct base boost of about 7 psi, the APC then assists the actuator to gain more boost. Running with base boost above say 8 psi mucks up the ECU & it negatively adapts, I think it would also put a fair strain on the turbo
 
#24 ·
To Prio, yeah, he disconnected the down pipe from the turbo to check if the flap was hanging free, but said it was ok, still all in one piece.

To Norman, so you reckon that I have too strong a spring in the actuator, making it impossible for the APC to control and make open? he has changed all my uprated stuff back to standard, fuel ecu, DI ecu. Is the fuel ecu connected/controllling the APC? The actuator with the 14-18 psi spring had the turnbuckle turned back inwards 2 turns to bring up the base boost too.

So I should have him change the FORGE actuator I have on the car with a basic standard one for now, to test if it boosts up yeah? If it does boost up with the standard actuator, then how can I have all my own bits put back on and work properly?
 
#25 ·
Just been on the fone to the Saab guy, and suggested about the actuator spring being too strong for the ecu/APC to control. He said, NORMALLY, were that the case, then it would OVERBOOST, rather than underboost. he said he will do a pressure test on the actuator again to check the diaphragm is ok inside.
 
#26 ·
If you disconnect the vac hose to the wastegate actuator, or better still just clamp it shut with mole grips and the wastegate actuator arm hasn't fallen off and you do not overboost then this leaves one of three options

1) the wastegate valve possibly missing, need to take exhaust off to check.
2) you have a big hole somewhere in the pipework or intercooler.
3) bits of metal from unknown source have wrecked the exhaust turbo vanes......I cannot see any other reason why you are only getting 2psi boost.
 
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