DeerHunter

It's been one of those summers with my fair-weather daily driver (the stroker '93 L.E. and not my track-mostly MSM, although that's had its fair share of issues). The first blow came a few days before my FM Summer Camp trip, when I discovered that I was losing coolant (the overflow tank emptied in less than a week). I didn't have time to deal with it so I shipped it off to a local enthusiast shop. It was difficult to diagnose as the leak only manifested when warm and under pressure. The culprit, as it turns out, was a failing water pump. I thanked my lucky stars that it was discovered before I hit the highway for a multi-thousand mile road trip. There was time to order the necessary parts (water pump, timing belt kit, etc.) and do the swap before the weekend. Unfortunately, my ATI damper didn't play ball and steadfastly refused to budge off the crank nose. When all was said and done, removal took most of the day and the mechanic left that evening for a week's holiday, with my car still in pieces. Scratch taking my Miata on a Miata trip (I had to rough it in the Audi).

I picked up the car a couple of weeks later and discovered, on my drive home, that the front anti-roll bar wasn't installed with the proper clearance to my A/C idler pulley. When I turned on the air conditioning, there was an unholy scraping sound. No problem, said the shop, bring it by and we'll stick it on the hoist and put it right.

The next afternoon, I started the car (A/C off) and pulled out the garage, waiting at the end of my driveway while the door closed behind me. Before I could continue, the engine stalled. No preamble, no stumble - it was like a light switch had been thrown. Strange! I cranked the engine and it made absolutely no effort to start. I checked fuel pressure (I have an in-car FP gauge) and everything appeared normal. Just in case, I switched out the main engine relay with a known-good unit - no change. At this point, the starter kicked back after some more cranking and then refused to do anything anymore. Mmmm!

I did some more troubleshooting. Battery voltage was nominal and there was no voltage drop at the alternator connection. Despite the fact that I'm convinced I have one of the best starter circuits in the NA world (resulting from years of trouble-shooting, parts replacement and various improvements stemming from an intermittent no-start issue), I decided that I would jumper the + to the solenoid, just to see if it would make any difference. It was with big-*** screwdriver in hand that I discovered that my starter motor wasn't attached to the bellhousing anymore, and was merely hanging on by the wires). While contemplating the situation, I caught the faintest whiff of fuel (foreshadowing alert).

Now, the intermittent start issue was solved by another shop last summer (the root cause was a failing clutch interlock switch, which was not apparent because I'd been using the FM-supplied bypass clip since my stroker installation). I figured that since they'd put everything back together, including the starter, they could deal with it. It was on a flatbed to their shop within an hour and I waited for their report.

There was some head scratching when they got a look at the car. Firstly, one of the starter bolts was missing. Secondly, the second bolt was still in place, but the entire tab/ear of the starter had torn loose. They were reluctant to use one of my spare starters (I replaced it more than a few times chasing the aforementioned intermittent non-start issue) since they also only used two bolts (Coles Notes: Early-model starters were big and heavy and were attached with 3 bolts plus a bracket on the front; Later starters were much lighter and the factory deemed the bracket no longer necessary; My donor block is a '99, hence no bracket, while my transmission case is an earlier version, so one of the bolt holes doesn't align with the later-style starter). After some research, we determined that an automatic '94-97 starter would allow us to use all three bolts with my particular engine/tranny combo.

Being an unusual part number, it took a week for the starter to get here (I spent the time going to see the eclipse in WY), along with a fresh set of bolts from the dealer. They installed it, wired everything up and... nothing. They pulled it again, bench-tested it successfully and then did some more head scratching. They put the car in gear and tried to turn over the engine by turning the rear wheels - it didn't budge. Removal of the spark plugs revealed that all cylinders were completely filled with fuel. Also, my oil level was about two litres high, diluted with excess fuel. Yikes! Obviously my fueling system was throwing a conniption fit. The initial stall was caused by hydrolock. Once the fuel drained past the rings, I was able to turn it over with the starter. As the cylinders filled up again when cranking, the second hydrolock torqued the starter motor right out of the bellhousing.

First thoughts centered around leaking injectors, a bad injector ground, or perhaps a blown Hydra ECU. A little further investigation revealed the actual cause:



Yup, that's my 8-year-old AEM fuel-pressure regulator, spraying high-pressure fuel out the vacuum port and directly into my intake manifold. I'm told that the root cause is a failed diaphragm and that it's not common. Lucky me.

After draining the excess fuel and all the oil, fluids were refilled and they tested piston stroke with a dowel (all were identical). A compression test confirmed 160 psi across all cylinders on the first compression stroke, so it looks like I dodged a bullet. The hydrolock occurred at idle, so there wasn't enough momentum to bend one of my H-beam rods. It means, hopefully, that a simple FPR rebuild kit will put my car back on the road and allow me to enjoy the waning days of summer. While it's been a royal PITA, I'm again thanking my lucky stars that it stalled in my driveway and not an minute later at speed, where some serious damage would have occurred (not to mention possible loss of control if the rear wheels locked up). Oh, the joys of keeping an older car on the road.

The Driver

Wait, so you were with Richard Dekker and Gordo @ Summer Camp? Man, I'd love to have met ya!

DeerHunter

It's possible you did, without realizing it. Richard was kind enough to let me use his ND at Friday's track day, where I managed 6th fastest time overall (and, I believe, fastest naturally-aspirated). Those NDs are good and Richard's is particularly well-sorted.

Gordon and I were both slumming it in our Audis. Not as much fun through the twisty stuff, but we sure were more comfortable in the summer heat.

The Driver

Now that would be funny, if we did meet by accident.

Sorry for your NA troubles, I've been following your build, over @ M.net, for almost a decade!