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RarlyL8 RarlyL8 is offline
Crotchety Old Bastard
 
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Join Date: Jan 2000
Location: Huntsville, AL
Posts: 13,623
Garage
Latest update. Remember the brand new Chinese fuel pump relay that failed on me a few months back? Oh you guys are gonna love this.
Had to follow up on the ignition gremlins this car has had and the saga to get them all fixed.
The latest "fix" was to remove the delay relay up in post #725 and replace it with a modern non-timed relay. The engine fired right up after the transplant. We had tested that delay-relay and it failed to close the connection when activating the relay portion, so we knew it was flaky.
Well I put the IC back on and drove the car ~25 miles then back to the shop with no drama. Running really well with the added bonus of no run-on when you turn off the key (yes!). Feeling confident I decided to take it home where it belongs. Got about 1 mile away from the shop and poof! engine shuts off like I tuned off the key. Pulled over and cranked it, nothing. Good lord what now. Replaced the new relay and no fire. Another ride of shame back to the shop.
SO we start the search again.
Pulled a spark plug, no spark.
Hit the key to position 2 and the pumps fire. OK problem is still ignition.
Pull the fuel pump relays and hit the key and hear the CDI buzz. What?
OK maybe this is intermittent so plug in the fuel pump relays and hit the key, cranks no start. CDI still buzzing.
OK we have power to the CDI but had no spark. Check spark at the plug again, no spark.
Pulled the coil wire and checked spark, no spark.
Pulled the distributor and checked spark, we have a spark.
Are you freaking kidding me, the BRAND NEW coil that was replaced last month is dead? Grabbed a coil off a 911 engine we are rebuilding and plugged it into the system. SPARK.
Un-freaking believable. I replaced the OEM coil a couple months ago when I was going through this same scenario along with the green wire and cap/rotor. That was the SECOND coil that I had purchased from Bosch, the 1st one had a post snap off when screwing on the tiny 8mm nut. I gave the Bosch rep an earful. His response was less than comforting. He admitted what we all now know, that all parts come from Asia and are junk. Quality control is a thing of the past and parts are re-badged by everyone.
SO I went through my old parts bin and pulled out the OEM coil. Replaced the new Bosch unit with the old coil, put the intercooler back on and fired up the engine first hit.
This is a tragedy, not only for me personally but for every vintage car enthusiast and my clients as well. I'm going to do some searching and see where the good coils are, if they exist. I have to find some confidence level to drive this car, and it just can't be done with these garbage parts.
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RarlyL8 Motorsports / M&K Exhaust - 911/930 Exhaust Systems, Turbos, TiAL, CIS Mods/Rebuilds
'78 911SC Widebody, 930 engine, 915 Tranny, K27, SC Cams, RL8 Headers & GT3 Muffler. 350whp @ 0.75bar
Brian B. (256)536-9977 Service@MKExhaust Brian@RarlyL8
Old 11-26-2017, 07:31 PM
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