Ross Posted November 20, 2007 Share Posted November 20, 2007 The wagon almostg stranded me half way down a beach last night.... Was driving along fine, then alll of a sudden ecs light comes on and engine stops making any real power.... It wont die, idles fine and the ecs light will go out if idling. Put any throttle on, and ecs lights up and very little power is produced at first, then (if at full throttle) the engine will abruptly power up for a second or two before dieing out again - this repeats as long as I have my foot flat. After stopping the engine for half an hour or so, it went fine and drove it home - it did the same thing for a minute or two on the way, but cleared up again. Being an ancient ea81t, the computer doesn't store codes, and I didn't manage to catch what they were while it was occurring. I'm thinking TPS or VAF...... any thoughts? Link to comment Share on other sites More sharing options...
daeron Posted November 20, 2007 Share Posted November 20, 2007 i thought "tps or flapper MAF" This is a switch-type TPS, not the potentiometer "sensor", right? another possibility that you didn't mention (doesn't mean you didnt check) is that of water getting into a plug of some sort.. my 280Z had a very very similar FI system to the early soob setup, and if any water got under the hood it somehow found its way to the TPS plug, which had a bad boot and let water sit inside the recess of the plug itself.. as a result, I mashed the gas pedal, engine would happily rev up to about 2300, and totally DIE until the tach needle jumped back down to about 1700, at which point the engine was right as rain again. The MAF could have a similar issue, or either one could have a dirty contact anywhere in the sweep that isnt the "idle" band. Link to comment Share on other sites More sharing options...
Ross Posted November 21, 2007 Author Share Posted November 21, 2007 i thought "tps or flapper MAF" This is a switch-type TPS, not the potentiometer "sensor", right? another possibility that you didn't mention (doesn't mean you didnt check) is that of water getting into a plug of some sort.. my 280Z had a very very similar FI system to the early soob setup, and if any water got under the hood it somehow found its way to the TPS plug, which had a bad boot and let water sit inside the recess of the plug itself.. as a result, I mashed the gas pedal, engine would happily rev up to about 2300, and totally DIE until the tach needle jumped back down to about 1700, at which point the engine was right as rain again. The MAF could have a similar issue, or either one could have a dirty contact anywhere in the sweep that isnt the "idle" band. yeah its the switch tps. Can rule out water i think, cos it was a dry day.... Just wish i could get it to do it again while i look at the ecs led! Link to comment Share on other sites More sharing options...
carfreak85 Posted November 24, 2007 Share Posted November 24, 2007 I have never had a problem like that, I wish I could be more helpful. Link to comment Share on other sites More sharing options...
Ross Posted November 24, 2007 Author Share Posted November 24, 2007 I got a code 22 out of it last night. apparently that means "Pressure or Vacuum Switches - Fixed Value". is that right? unfortunately that doesn't really help much, since I can't think of any pressure /vacuum sawitches that i still have hooked up..... Link to comment Share on other sites More sharing options...
carfreak85 Posted November 25, 2007 Share Posted November 25, 2007 Even the factory pressure switch? I won't have my FSMs or supplements until later tomorrow. I'll look then. Link to comment Share on other sites More sharing options...
Ross Posted November 25, 2007 Author Share Posted November 25, 2007 That boost switch? I didn't think the computer used that - isn't it just for the dash light? Link to comment Share on other sites More sharing options...
ausubaru92 Posted November 25, 2007 Share Posted November 25, 2007 There should be 2 boost switches, one for the dash light (set at 2psi), and the other for the ecu (set for i think 8psi). You should be able to read stored codes, there are 2 pairs of connectors. There is a configuration for reading stored codes. Link to comment Share on other sites More sharing options...
Ross Posted November 25, 2007 Author Share Posted November 25, 2007 There should be 2 boost switches, one for the dash light (set at 2psi), and the other for the ecu (set for i think 8psi). You should be able to read stored codes, there are 2 pairs of connectors. There is a configuration for reading stored codes. That is for an ea82t, mine is an ea81t. A different beast. ea81t has only 1 boost switch, and cannot store codes. Link to comment Share on other sites More sharing options...
carfreak85 Posted November 26, 2007 Share Posted November 26, 2007 Just uploaded some scans of the FSM EA81T supplement. Check out my photos, also let me know if you need any other pages. Link to comment Share on other sites More sharing options...
Ross Posted November 27, 2007 Author Share Posted November 27, 2007 Cheers. I think my problem may actually have nothing to do with the code 22 that I get if i go for a drive with the green connectors connected. I suspect that all this code is saying is that the egr vacuum switch is not operating -which is not surprising, since it is not connected to any vacuum lines due to the egr system having been removed when I rebuilt this engine. This has been the case for a couple of years now, and has never caused a problem - I think the ecs just gets fussy about this when in test mode. In that case, it means that the problem has not occurred during any of my test runs (makes sense since i didn't notice it). Have been driving a fair bit lately and it hasn't happened again. Anyway, after some thinking, I've pretty much narrowed it down to either a problem with the airflow sensor, idle switch or their respective wiring. Cant be anything to do with ignition, since problems after the mag pickup wont cause the ecs light, and problems with the pickup or associated wiring etc will cause the tachometer to stop working, which it did not. Auxiliary sensors like the coolant temp sensor, outside air temp, knock sensor, and O2 sensor either shouldn't make such severe symtpoms, or should prevent the engine idling properly (mainly in the case of CTS). Fuel supply problems would be very unlikely to give such frequent and sudden changes between next to no power and full power, since it will take a finite time for the pump to bring the lines up to pressure, as well as for the lines to loose pressure once the pump has stopped. I'm not sure exactly what the ecs does when the idle switch is activated, but i suspect that it may try to bring the engine speed down if it were higher than idle by cutting fuel supply. The ecs light would in this case likely be caused by both the idle and WOT switches being closed at the same time - another possibility is that the ecs didn't like the large airflow measurement it was getting with the idle switch closed. The other option is the airflow meter - maybe this was just sending the ecs a signal that didn't make sense. I guess it could also be a problem with the injector circuit. Anyone know where the wiring for the injectors separates into four individual injectors? Other than that, it could be a dry joint etc. in the ecs itself....... Anyway, I'm pretty much going to have to wait for it to happen again before I can really diagnose it properly....... But any thoughts suggestions welcome.... Link to comment Share on other sites More sharing options...
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