I have been lurking this forum for a couple years now, and the knowledge I have gained has been invaluable in maintaining and modifying my FD. Thank you all for contributing. This is my first post of any substance because I have not until now run into any problems that could not be solved with a forum search, and have not had the requisite experience to give informed advice to others.

I set out to replace a badly leaking water pump and to diagnose a fuel problem that was causing the engine to crank with no hint of combustion. I replaced the water pump and gasket, the water pump housing gasket, the turbo coolant lines, and decided that this was a good time to inspect my fuel system and do the hose job. So I removed the solenoid rack and replaced all of the hoses, removed the fuel rail and replaced the hoses, FPD and insulators, and sent the injectors out to be cleaned and balanced. Putting it all back together, I threw in new plugs and wires and replaced all of the gaskets. In the course of my diagnosis, I found that the lack of fuel delivery was due to a badly corroded contact on the EGI relay, which I cleaned.

Once it was back together, I tried to start it before filling it with coolant, to make sure the engine would at least start. It cranked with combustion, but was very difficult to start, and once I got it started, it idled poorly with what looked and smelled like exhaust gas coming from the area of the LIM. After shutting it down (it ran for less than a minute), I opened the coolant fill cap and discovered, to my horror, many sizable aluminum shavings (about 1mm) stuck to the walls of the thermostat housing.

My questions are these:

1. I suspect that I may not have sufficiently tightened the ACV nuts. Would a leak at the ACV gasket cause a vacuum leak which would make the engine difficult to start and cause a poor idle? Would the lack of vacuum then cause the EGR valve not to close properly, recirculating exhaust gas into the LIM during idle which then escaped through the leaking ACV gasket?

2. The water pump housing had been slightly worn by the impeller of my old water pump, which was badly out of tolerance. I would assume that a new water pump would fit loosely in this worn housing, and not cause any additional wear. Is it possible to overtighten the water pump and housing bolts to the point where the impeller of a new pump would substantially cut into an already worn housing? Has anyone experienced this?

I will of course disassemble everything again to investigate the problem, but before I do, I would appreciate any comments if anyone has insight or experience with these problems that could point me in the right direction. It was an unpleasant surprise to finally get my car back together with many new parts and get hard starting, strange exhaust leaks, and aluminum shavings in my coolant system...

 

Don't start the engine without coolant! Flush the system and see what comes out...Then fill it up and try it again...

 

Thank you for your feedback! I never intended to run the engine at all, just to see if I had fixed my fuel delivery problem and if it would fire. It ran for about 10 seconds without coolant - could that have damaged the pump?

 

No, it wouldn't damage the pump. Perhaps when you were scraping/cleaning off old gasket material some small shavings and particles off the WP housing flew around and got into the system? Even so, if it's just a little it shouldnt be of any consequence. Perhaps it was the result of the previous bad water pump.

A leaking acv gasket would cause either an exhaust leak or an intake/vacuum leak, neither of which should make the car hard to start...but it could affect idle quality afterward. Sounds like you might have screwed up installation of the lower fuel injector orings. Taking a few seconds to crank wouldnt be unusual after disconnnecting the fuel lines and letting some drain out, btw.