cobcob Posted August 11, 2007 Share Posted August 11, 2007 As the title says... Here's the rundown, installed replacement MAF, re-connected the knock sensor, that has cleared the codes. Fixed 1 vacuum leak, re-attached the exhaust on the drivers side (still a little loose I think) one of the bolt holes on that side was stripped out. The boost light does not come on, the engine will not idle without a little gas pedal. I managed to get it to idle by removing the piece from the turbo to the throttle body, it'll sit at around 1100 rpm, it'll idle a bit slower if I put my hand over the inlet on the throttle body. With the turbo - throttlebody piece in place it will not maintain a steady idle. There's no codes in the ECU at all, looking for suggestions... timing perhaps? Link to comment Share on other sites More sharing options...
cobcob Posted August 11, 2007 Author Share Posted August 11, 2007 BUMP... Need help here guys... I'm going to check the intake manifold later to see if maybe the gasket is bad... That's one problem with buying someone else's project car, you're never certain what might be loose or leaking Link to comment Share on other sites More sharing options...
Gloyale Posted August 11, 2007 Share Posted August 11, 2007 Have you checked the auxillary air valve? The tube comes off the bottom of the "subaru Turbo" cast piece, goes to the AAV, then goes in top the side of the throttle body. If you unbolt the AAV from the thermostat housing, you should be able to verify if it is sticking closed. If it is sticking closed it could be causeing low idle/stalling until warm. It should be open when the engine is cold and closed warm. Inspect you're intake boot for cracks and leaks as welll. Also have you tried simply raising the idle. There is an idle adjust screw. It is in a receessed hole in the back portion of the throttle body. You can see it if you look straight down from over the throttle bore. It's behind it, about 3/8" dia. Flathead screw in a recessed hole. IIRC screwing it in lowers idle, screwing it out Raises. Link to comment Share on other sites More sharing options...
Sonicfrog Posted August 11, 2007 Share Posted August 11, 2007 What is the history of the car? Was it running when you bought it? If the head gaskets were replaced recently, then timing does sound like a good thing to look at, especialy if you're no longer throwing codes. Oh, and double check to make sure that the rotor is fastened to the distributor shaft. The turbo's used a little screwto hold it in place. Link to comment Share on other sites More sharing options...
cobcob Posted August 11, 2007 Author Share Posted August 11, 2007 Thanks guys! History's somewhat unknown, the guy I bought it from was doing some work on it but it was in 'limp mode' when I bought it. I know he replaced the header pipe and had been tinkering with the MAF. I'll check the AAC and rotor, it looks like there's a reasonably new dizzy cap on it so that may be a contributing factor! I haven't messed with the idle speed screw yet, seems that I've got a leak someplace otherwise putting my hand over the throttle body intake would have killed the engine all together... Link to comment Share on other sites More sharing options...
Gloyale Posted August 11, 2007 Share Posted August 11, 2007 So are you saying you can get it running with nothing at all attached to the throttle body? No tube from the MAF? I would think it would die with no Maf signal? Anyhow. The AAV supplies Auxillary Air for warm-up idle. Placing you're hand over the throttle body won't stop air from passing through the AAV into the intake. For the test you're trying, you'd need to plug the AAV hose. Confusing, but hang in there, you'll track it down. We'll help Link to comment Share on other sites More sharing options...
cobcob Posted August 11, 2007 Author Share Posted August 11, 2007 with the MAF still plugged in but no tube from the turbo to the intake it will idle fine, around 1100 rpm or maybe a bit higher. putting my hand over the throttle body intake will slow the idle but not completly stop the vehicle. Link to comment Share on other sites More sharing options...
cobcob Posted August 11, 2007 Author Share Posted August 11, 2007 AAV checks fine... Removed the 'Subaru Turbo' cast piece, plugged the line to the AAV and started the car, runs at about 2000 rpm, hand over the intake and slows right down and almost dies. Think there's still a vacuum leak in it somewhere, I can hear the hissing and it's driving me insane trying to find it! Link to comment Share on other sites More sharing options...
Reveeen Posted August 11, 2007 Share Posted August 11, 2007 Idle (or as close as you can get) vacuum? followed by a compression check. Link to comment Share on other sites More sharing options...
Gloyale Posted August 12, 2007 Share Posted August 12, 2007 OK. I think the way you are trying to test this is more trouble than troubleshooting. If this were a Non turbo, fuel injected car, removing the tube from the throttle body would make it die. This is because no air would be pulled through the MAF, seeing zero air, it would give little or no fuel. In you're case with the turbo, the car is only running because the Turbo is pulling in air through the MAF as it is driven by the exhaust. The MAF sees air passing through and meters fuel for that. But this is a different amount of air than is actually being sucked down the throttle body by engine vacuum. So of course it will never run normal in this manner. Also in this case since you have the outlet of the turbo open to atmosphere, it never pressurises. So you won't have any boost to build up and activate the wastegate. I'm not sure but that could be a bad situation for the turbo. It does explain why there is no boost light. I would hook it all back up, and then try to troubleshoot. Link to comment Share on other sites More sharing options...
Reveeen Posted August 12, 2007 Share Posted August 12, 2007 Of course, if there was a bad, or tight, intake valve it would be behaving much as you describe. Link to comment Share on other sites More sharing options...
cobcob Posted August 12, 2007 Author Share Posted August 12, 2007 If this were a Non turbo, fuel injected car, removing the tube from the throttle body would make it die. This is because no air would be pulled through the MAF, seeing zero air, it would give little or no fuel. I thought of that late last night. Put it all back together and I've got a non-idling situation. I have to give it a bit of gas to get it to stay running, it'll run for about a second or 2 and then die off. I hardly have time to crank it over (reaching through the window) and then jump to the front of the car and grab the throttle cable to try and keep it running. If I back off the gas it'll sputter and jerk, maybe run for a second or so and then die. Link to comment Share on other sites More sharing options...
Gloyale Posted August 12, 2007 Share Posted August 12, 2007 Are you getting any trouble codes. make sure the boot from MAF to turbo has no leaks. Also will it run with the test connectors hooked up? Really try adjusting the idle just a tad with the idle screw. Link to comment Share on other sites More sharing options...
cobcob Posted August 12, 2007 Author Share Posted August 12, 2007 No trouble codes, no leaks, haven't tried the test connectors yet... I guess I'll try the idle screw tonight when I get home... Link to comment Share on other sites More sharing options...
cobcob Posted August 14, 2007 Author Share Posted August 14, 2007 OK, Tried it last night with the test connectors hooked up, still no idle. tried adjusting the idle speed screw, still no idle. Found a vacuum leak in the line to the brake booster, also seems that the check valve in that line is bad because the brake pedal 'floats' with the RPM of the engine (more gas, the pedal moves away from the floor) Link to comment Share on other sites More sharing options...
joostvdw Posted August 14, 2007 Share Posted August 14, 2007 have you re-checked your timing belts? also the intake manifold gaskets can be installed up side down and fit but they don't seal (don't ask me how I know that ) try spraying some carb cleaner around hoses and fittings, if you spray it onto a leak, the idle will jump. Link to comment Share on other sites More sharing options...
cobcob Posted August 14, 2007 Author Share Posted August 14, 2007 I haven't checked the timing yet, need to get a timing light. I have no idea if the intake gaskets are upside down or not, the car is in the same condition that I bought it in, I'm about to the point of pulling the engine entirely and starting from the ground up (so much for a quick repair project!) Link to comment Share on other sites More sharing options...
joostvdw Posted August 14, 2007 Share Posted August 14, 2007 I haven't checked the timing yet, need to get a timing light. I have no idea if the intake gaskets are upside down or not, the car is in the same condition that I bought it in, I'm about to the point of pulling the engine entirely and starting from the ground up (so much for a quick repair project!) I don't mean ignition timing, I mean cam timing, with the timing belts on the front of the engine Link to comment Share on other sites More sharing options...
cobcob Posted August 14, 2007 Author Share Posted August 14, 2007 *slaps forehead* nope haven't had the time to wrestle the covers off yet... Link to comment Share on other sites More sharing options...
john in KY Posted August 15, 2007 Share Posted August 15, 2007 OK,Tried it last night with the test connectors hooked up, still no idle. tried adjusting the idle speed screw, still no idle. Found a vacuum leak in the line to the brake booster, also seems that the check valve in that line is bad because the brake pedal 'floats' with the RPM of the engine (more gas, the pedal moves away from the floor) Remove the vac line going to the PB and plug it with a bolt. My XT6 will idle all day with the air intake tube removed. Fairly sure it will idle even with the airflow meter unplugged. When the engine is idling, essentially no air goes pass the throttle plate in the throttle body because it is in the closed position. "Idling" air is the function of the IAS system. If the IAS allows too much airflow then the idle increases. Too little and the engine dies. Just a few thoughts. Link to comment Share on other sites More sharing options...
cobcob Posted August 15, 2007 Author Share Posted August 15, 2007 Edit... scratch that... I'm an idiot Link to comment Share on other sites More sharing options...
cobcob Posted August 21, 2007 Author Share Posted August 21, 2007 OK, officially flummoxed... yep, flummoxed... checked the cam belts just now, they're set correctly, middle mark on the flywheel lined up with the mark on the housing, left sprocket mark is down, right sprocket (drivers) is pointing up. Checked the plug wires are all connected correctly and the rotor is firmly attached to the shaft... any other suggestions? One thing I did notice when removing my battery for charging is that there's a black wire coming out of the fusible link block that goes directly onto the +ve terminal of the battery I assume that's the correct spot for it but there's no crimp terminal on the end of the wire, it's just sandwiched under the bolt on the battery I'll be in the garage threatening the engine with a 12 gauge to see if I can scare it into some form of normalcy... Link to comment Share on other sites More sharing options...
hyrysc Posted August 21, 2007 Share Posted August 21, 2007 OK, officially flummoxed... yep, flummoxed...checked the cam belts just now, they're set correctly, middle mark on the flywheel lined up with the mark on the housing, left sprocket mark is down, right sprocket (drivers) is pointing up. Checked the plug wires are all connected correctly and the rotor is firmly attached to the shaft... any other suggestions? One thing I did notice when removing my battery for charging is that there's a black wire coming out of the fusible link block that goes directly onto the +ve terminal of the battery I assume that's the correct spot for it but there's no crimp terminal on the end of the wire, it's just sandwiched under the bolt on the battery I'll be in the garage threatening the engine with a 12 gauge to see if I can scare it into some form of normalcy... man, that is a real bummer. I sure wish I could help, but I just do not know. you might just want to ditch the turbo and intake and just go NA. Just a thought... but what do I know. Link to comment Share on other sites More sharing options...
85T-REX Posted August 21, 2007 Share Posted August 21, 2007 Originally Posted by cobcobinstalled replacement MAF Did you have the same results with both MAFs? Could be one, or a combination, of three things: 1. MAF not operating properly. -- Be sure the flap opens and closes all the way and the connection is good and clean. 2. Damaged turbo. -- Due to the replacement of the header pipe. Make sure the intake lines are clear and the turbo spins freely. That may be why the turbo light doesn't come on. 3. Ignition timing not advanced far enough. -- Should be about +20 deg. Because it's affected so drastically by the removal of the Turbo intake pipe, it seems to be a combination of 1 and 2. My turbo won't run without that pipe in place. Also, make sure your oil filler tube is tight and the cap seals tight. rex Link to comment Share on other sites More sharing options...
Sonicfrog Posted August 21, 2007 Share Posted August 21, 2007 I wonder if previous owner screwed with the disty timing? It's real easy to set it 180 deg. from TDC. I actualy got mine to run, but it ran crappy. I would line up the cams and recheck the disty setting. I have blown head gaskets on Murphy, the $500 87 T-Wag, and every time I have put it together, I have had a heck of a time geting 'er going again, thus the nickname "Murphy"!!! And it's usually (always :-)) my fault. Link to comment Share on other sites More sharing options...
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