Compression test specs
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Compression test specs
I just to a compression test on my none starting 95 90q 2.8 and got reading of 125psi across all cylinders except No3 (145psi). Does anyone have specs I can compare it to. It has bout 180k on the ODO and I think the compression is a too low. My next step is to pull the heads and take a closer look into things.
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Well that puts me within spec, I have no idea what to check again
Ive checked Timing, I have spark, fuel (bench tested fuel pump, Checked pressure), compression(125 across & 145 on cyl 3), Checked all my trigger signal components (with Ossilloscope, have good sine wave forms, 5v+). Replaced CKP & CAM sensors, I have RPM signal, Jumped starter switch terminals (Dealer even replaced the switch cus they thought it was the issue) changed plugs, Blocked off the EGR valve, tryd starter fluid, Removed the exhaust from manifold (Down pipe). Empyd gas tank and used fresh fuel. Checked all posible ignition wiring for continuity from the component to the ECU connectors. ECU has battery volt from ignition and Battery, all grounds checked. Tryd my ECU in a diff car and it ran fine (did not drive it). What cud I be Missing so far? Dealer say it needs an ECU after checking it for 3months.
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Ya might wanna at least attempt plugging in another ECU in your car instead of vise-versa...
I can certainly understand the frustration of something like this. I blew over $2k once in the early 70's trying to diagnose a miss in a BMW only to find I had a single spark plug that was brand-spanking new with a broken/interrupted electrode behind the ceramic insulator that came that way from the factory but didn't manifest itself for almost 2k miles. Who woulda thunk it!?! But this was long before the day of computerized diagnostics that would've been all over that spark plug like white-on-rice.
When these things defy reason/logic it's usually time to start being unreasonable/illogical right along with em.
When these things defy reason/logic it's usually time to start being unreasonable/illogical right along with em.
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Im having trouble gettin the proper ECU though
Ive payed for 2 so far and they never get me what I need. Email the sellers back and they dont respond and I dont blame them. Mine is numbered (MMS-311, 8A0 906 266E) the last one i got from a forum member was a MM313. They lucky I dont like puttin people on blast but i got it for cheap so I count my loss.
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if you're telling them specifically MMS311 and they're sending you something else I would hold...
them accountable/culpable for sending you something else. I mean it's written on the lable on the outside of the box for chrissake!
Short of that you could always pick one yourself from a junkyard or at least have a seller send you a picture of the identification tag before you commit to purchasing. If you continue to buy "sight-unseen" it only adds to the cost of getting the correct one so "cheap" may not be the best you can do in this instance.
I realize there's no easy answers but getting the correct ECU should not be a problem as there's a gazillion MMS311's out there!
Short of that you could always pick one yourself from a junkyard or at least have a seller send you a picture of the identification tag before you commit to purchasing. If you continue to buy "sight-unseen" it only adds to the cost of getting the correct one so "cheap" may not be the best you can do in this instance.
I realize there's no easy answers but getting the correct ECU should not be a problem as there's a gazillion MMS311's out there!
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Thread Starter
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Could you point me to a reliable source then pls.....
I posted my request on the forum bout twice already and got the wrong one on the second shot. There arnt any junk yards in my area that dismantle audis that I knw of but I'll look into it again, deftly asking for a pic this time around.
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if you cannot find someone parting a car on AW or Audifans etc try...
car-part.com. They're a national salvage yard clearing house. And there's several nationally known salvage yards that specialize in Audi like Dad's on the left coast and Shokan/Audi Only & others on the right coast.