Boosted 70z Posted July 26, 2006 Share Posted July 26, 2006 I have a 70 240z w/ an 83 l28et running an SDS standalone. It was running fine one night when I was driving home from work doing 45 when I tried to speed up and had no power. I pulled over and it idealed low, I gave it full throttle and nothing for about 30 sec. and then started reving slowly. I could hear boost building up but no power. I was close to home so I tried to limp it back. Then it started to overheat. I popped the hood again and it was steaming and the radiator was wistling like a tea kettle. I thought it was the head gasket so I ran a compression check, and it all turned out good. Has anyone had anything like this? Is something other than the head gasket rob power and loose coolant or do I have 2 separate problems? Thanks. Quote Link to comment Share on other sites More sharing options...
TimZ Posted July 26, 2006 Share Posted July 26, 2006 Is your distributor still fastened down? Quote Link to comment Share on other sites More sharing options...
veritech-z Posted July 26, 2006 Share Posted July 26, 2006 Intake hose between MAF and throttle body come loose? Or is SDS a MAP based system? Quote Link to comment Share on other sites More sharing options...
thehelix112 Posted July 26, 2006 Share Posted July 26, 2006 One way to check if you are leaking coolant into the engine is just to pull all the plugs and crank it over. If its leaking it'll shoot water out. I've had perfect compression readings with a blown head gasket, very wierd. Also obviously check timing/basics. Dave Quote Link to comment Share on other sites More sharing options...
orklc Posted July 27, 2006 Share Posted July 27, 2006 Tell me more about the overheating. Where both fans running? I know you have no distributor, and if the engine starts then the magnets in the SDS are being read. Have you made any adjustments to the SDS? Is it running in all six cylinders or have you lost a couple? How much boost where you running? Need more information to help. Ken Quote Link to comment Share on other sites More sharing options...
savageskaterkid Posted July 27, 2006 Share Posted July 27, 2006 I have the same exact problem on my car, but have niether the patience or want to even put in the time to diagnose that motor. Does it have a problem with bogging while getting off the line, and you have to barely engadge the clutch to move-like slip it REALLY BAD. Quote Link to comment Share on other sites More sharing options...
Boosted 70z Posted July 27, 2006 Author Share Posted July 27, 2006 Tell me more about the overheating. Where both fans running? I know you have no distributor' date=' and if the engine starts then the magnets in the SDS are being read. Have you made any adjustments to the SDS? Is it running in all six cylinders or have you lost a couple? How much boost where you running? Need more information to help. Ken[/quote'] The fans were working and I think all the cylinders were running. I haven't had the car long and I haven't messed with the tuning yet. I'm running 10lbs. of boost. When it was overheating there was alot of steam and coolant was dripping from the frame under the radiator. When I ran the compression check I pulled all of the spark plugs and no water came out. Now the radiator is empty. I'm starting to think that I have two separate problems. Its still starts and ideals and if i hold down the gas it will slowly rev up after 30 sec or so, so I can move just no power. And I have coil packs. Quote Link to comment Share on other sites More sharing options...
TimZ Posted July 27, 2006 Share Posted July 27, 2006 Its still starts and ideals and if i hold down the gas it will slowly rev up after 30 sec or so' date=' so I can move just no power. And I have coil packs.[/quote'] Sorry - I guess I was thinking of MegaSquirt. Still wouldn't hurt to check/verify the timing - that's where I was headed with that. When you say that you haven't messed with the tuning, I'm assuming that you do have some sort of advance curve programmed in? Quote Link to comment Share on other sites More sharing options...
orklc Posted July 27, 2006 Share Posted July 27, 2006 On the issue of overheating.... Go to Auto Zone and buy a cooling system dye and added to your coolant/water. Run the engine and use a UV light and the UV Lenses that the auto parts sells to check for traces of dye in your engine oil, spark plugs or exhaust pipe. On the issue of power.... the SDS uses the TPS to sense the level of opening on the throthle as well as the MAP sensor. In one of the gauge modes of the SDS you should be able to see the actual readings for both parameters and check if they are doing what they are supposed to be doing. TPS values go up as you press the pedal. MAP measures vacuum/boost. You should have about 16 lbs of vacuum at idle. Let me know what you find. Have you read your spark plugs to see if they look ok? Ken Quote Link to comment Share on other sites More sharing options...
240Zed Posted July 27, 2006 Share Posted July 27, 2006 When was the last time you checked the coolant levels before it overheated? Quote Link to comment Share on other sites More sharing options...
Z-Gad Posted July 27, 2006 Share Posted July 27, 2006 Another thing that you may want to check is see whether your crankshaft pulley bolt has backed out. I'm with Tim, verify timing. It is also possible that the outer ring where the magnets are attached has spun (It only takes a few degrees to throw the timing off). I have had both of these instances happen when I was running SDS. Regards, Mike Quote Link to comment Share on other sites More sharing options...
Boosted 70z Posted August 3, 2006 Author Share Posted August 3, 2006 Alright, I changed the oil and put coolant in it. I also changed the spark plugs (old ones were black from it running rich). It will rev to 1k and stay there now. The fuel pressure regulator reads about 38. I'm not sure how to check the timing with the coil packs if someone could help out there. I put the uv dye in and theres some small leaks around the bottom of the radiator (at the drain plug and somewhere on the lower hose) but they aren't leaking much at all. Oh, i bought this car from cjarloz back in june so you guys from orlando may have seen it before. Quote Link to comment Share on other sites More sharing options...
Kennysgreen280zt Posted August 3, 2006 Share Posted August 3, 2006 Another thing that you may want to check is see whether your crankshaft pulley bolt has backed out. I'm with Tim' date=' verify timing. It is also possible that the outer ring where the magnets are attached has spun (It only takes a few degrees to throw the timing off). I have had both of these instances happen when I was running SDS. Regards, Mike[/quote'] I was going to say the same thing, I had a very similar problem with mine. As for the SDS timing, if it was setup correctly you should just be able to put a light on the #1 cyl like normal, and check it with the timing marks. I dont remember, but there should be a window in one of the gauge modes that will let you see what timing number you should be seeing at idle. Ah here it is, if you check out http://www.sdsefi.com you can look at the manual. Also they are very helpful over the phone for tech calls. Also check to make sure your mixture knob didnt get knocked around at all. I had that 'issue' once too. Its been a while since ive fooled with SDS, so this is all ive got as far as advise. Hope it helps Quote Link to comment Share on other sites More sharing options...
Boosted 70z Posted August 31, 2006 Author Share Posted August 31, 2006 Alright, I still can't figure it out. I had a mechanic look at and he said that everything mechanically checks out. He changed the water pump because it was leaking (Which must have been why i lost coolant). Right now its hard to get it started and even then it runs rough and won't rev. As for the magnets, they look to be ok based on marks on the pully. If it was thrown off how would I adjust it? And does anyone know anyone in jax, fl that can help? Quote Link to comment Share on other sites More sharing options...
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