Brought home for the first time.
#31
Nordschleife Master
Its more likely the smells were the car not running correctly. A misfire can cause hugely rich running, as the O2 sensor detects more oxygen in the exhaust gas and assumes the car is lean, so the ECU dumps in more fuel.
Seriously, go pick up the old cats - before the shop sells them.
Then start with the basics - checking plug wires, caps/rotors, O2 sensor, etc.
#33
Administrator - "Tyson"
Lifetime Rennlist
Member
Lifetime Rennlist
Member
He had a famous quote during the war:
"These engines are the fastest in any tanks in the European Theater of Operations, forwards or backwards. You see, man, we like to feel we can get out of trouble, quicker than we got into it."
#34
Drifting
The man who designed the reverse gear in the 928 was a retired tank engineer / driver from WWII.
He had a famous quote during the war:
"These engines are the fastest in any tanks in the European Theater of Operations, forwards or backwards. You see, man, we like to feel we can get out of trouble, quicker than we got into it."
He had a famous quote during the war:
"These engines are the fastest in any tanks in the European Theater of Operations, forwards or backwards. You see, man, we like to feel we can get out of trouble, quicker than we got into it."
Ryalex, your first lesson is learned, don't let anyone screw with your 928. Ask here first or search.
I don't know where the O2 bung is on an 85 US but if that is connected to the cat, maybe they messed up. Depending on the smog rules in NV for an 85 the only cats I would use are hi-flow aftermarkets like the ones I have, they will add power not subtract.
And I SURE hope there wasn't any welding involved in the new exhaust install.
#36
Advanced
Thread Starter
I hope you kept the original cats. With your cars mileage, odds are they're just fine. 928 cats are exceptionally long-lived; they're good for around 200k miles of running.
Its more likely the smells were the car not running correctly. A misfire can cause hugely rich running, as the O2 sensor detects more oxygen in the exhaust gas and assumes the car is lean, so the ECU dumps in more fuel.
Seriously, go pick up the old cats - before the shop sells them.
Then start with the basics - checking plug wires, caps/rotors, O2 sensor, etc.
Its more likely the smells were the car not running correctly. A misfire can cause hugely rich running, as the O2 sensor detects more oxygen in the exhaust gas and assumes the car is lean, so the ECU dumps in more fuel.
Seriously, go pick up the old cats - before the shop sells them.
Then start with the basics - checking plug wires, caps/rotors, O2 sensor, etc.
I bought it knowing that it was smelling rich and that the brakes were shot (and admittedly I worked them down to a price that reflected that), so I'm trying not to get worked up about this minor setback.
#37
Nordschleife Master
You're using a shop recommended by other 928 owners?
You need to - even most "Porsche shops" are woeful when it comes to these cars. 928's have higher complexity than any other contemporary Porsche (or later ones, where OBD-II diagnoses faults for you). That, coupled with low production numbers means most Porsche shops haven't actually seen enough of them to understand the issues/risks/procedures.
If you haven't, please do a search here for recommended shops in Nevada!
(asking a shop if they know 928's is a bad idea).
Please don't take this as criticism or talking-down to you - we just see a lot of new owners get badly badly burned, for thousands of dollars, by using local porsche or "german specialist" car shops.
You've got a great starting point for a 928, and it should be pretty close to running nicely!
Things it probably needs new ones of are: MAF, plug wires, spark plugs, caps/rotors. Coupled with a test to make sure there's no vacuum leaks around the intake manifold, that should be enough to get it running nicely - unless the muffler shop have damaged the O2 wiring, in which case add a factory sensor.
Nicole's point about the cats is spot on - the muffler shop will likely make more money selling your old cats than the new cats cost. Even if they want to charge you $50 to keep the old ones, do it (assuming they still have them).
You need to - even most "Porsche shops" are woeful when it comes to these cars. 928's have higher complexity than any other contemporary Porsche (or later ones, where OBD-II diagnoses faults for you). That, coupled with low production numbers means most Porsche shops haven't actually seen enough of them to understand the issues/risks/procedures.
If you haven't, please do a search here for recommended shops in Nevada!
(asking a shop if they know 928's is a bad idea).
Please don't take this as criticism or talking-down to you - we just see a lot of new owners get badly badly burned, for thousands of dollars, by using local porsche or "german specialist" car shops.
You've got a great starting point for a 928, and it should be pretty close to running nicely!
Things it probably needs new ones of are: MAF, plug wires, spark plugs, caps/rotors. Coupled with a test to make sure there's no vacuum leaks around the intake manifold, that should be enough to get it running nicely - unless the muffler shop have damaged the O2 wiring, in which case add a factory sensor.
Nicole's point about the cats is spot on - the muffler shop will likely make more money selling your old cats than the new cats cost. Even if they want to charge you $50 to keep the old ones, do it (assuming they still have them).
#38
Advanced
Thread Starter
I may or may not have had them take those off and put on straight pipes. Just to try it out. Allegedly. I've used the muffler crew a few times on other cars, they're friends of friends. They kept the cats for now as we troubleshoot the fuel issue.
Actually a generalist shop whose owner is a client. Hence, we trade legal for mechanical. For their guy this is a fun project, they get excited about it. It's not a volume place so it's not rushed around.
Dropping it off tomorrow for the major/tune. I'm leaving for my first non-Christmas, more-than-3-day-weekend vacation in 6 years so I'll be incommunicado for a week.
#39
Drifting
My point on welding, often welding is involved when building a new exhaust, usually MIG at shops, TIG on my custom set-up. BUT the important point is that unless you unplug both brains prior to the welding, there is a good chance they will be fried and need to be replaced/repaired. The poor running you describe is similar to a bad brain, or other things.
#40
Advanced
Thread Starter
My point on welding, often welding is involved when building a new exhaust, usually MIG at shops, TIG on my custom set-up. BUT the important point is that unless you unplug both brains prior to the welding, there is a good chance they will be fried and need to be replaced/repaired. The poor running you describe is similar to a bad brain, or other things.
#41
Rennlist Member
Welding is big time electrical forces; you are melting a metal rod by the heat generated basically. Electrons under huge amps will find a way to screw up the tender insides of a computer board or who knows what else. Anybody who welds should know enough to take this precaution though.
#42
Advanced
Thread Starter
So the car is a MY 1986 with late 1985 manufacture date. I ordered the TB/WP and tune kits from Carl and the shop called me over to show me that my car's water pump they removed is different from the one that arrived. It has a mount for a pulley where the new one just has a bolt hole. We assumed then that the 86 has some more components to make that pulley attach.
Sure enough, we see that the car had an "84" stamped pump while the one that we got is the "86" I ordered. They're pretty creative and made a mount for the 86 that fits the pulley and the bolt. But we were surprised to see the mismatch in parts like that.
Sure enough, we see that the car had an "84" stamped pump while the one that we got is the "86" I ordered. They're pretty creative and made a mount for the 86 that fits the pulley and the bolt. But we were surprised to see the mismatch in parts like that.
#43
Drifting
So the car is a MY 1986 with late 1985 manufacture date. I ordered the TB/WP and tune kits from Carl and the shop called me over to show me that my car's water pump they removed is different from the one that arrived. It has a mount for a pulley where the new one just has a bolt hole. We assumed then that the 86 has some more components to make that pulley attach.
Sure enough, we see that the car had an "84" stamped pump while the one that we got is the "86" I ordered. They're pretty creative and made a mount for the 86 that fits the pulley and the bolt. But we were surprised to see the mismatch in parts like that.
Sure enough, we see that the car had an "84" stamped pump while the one that we got is the "86" I ordered. They're pretty creative and made a mount for the 86 that fits the pulley and the bolt. But we were surprised to see the mismatch in parts like that.
Mj
#44
Advanced
Thread Starter
Ok, now I'm starting to get frustrated with this major power loss issue. As described before, the car just will not pick up and when in gear won't go above about 2000-2500 rpm even at WOT. Feels like I have about 60hp. The firing is smooth but it bucks a bit at 2500rpm.
The new timing/water pump and tune kit is done. Today I put in a clean, used MAF (which I had hosed down with CRC MAF cleaner) and Jetronic fuel brain I bought from Ducman82. The mechanic checked the fuel lines before and said they looked fine.
The car turns over well now and runs smoothly at idle. The last timing belt was very old and off time by two teeth. Seems like I'm getting okay spark. It *sounds* great. But no power is coming out.
Any ideas?
Could relays or the temp II sensor cause this? Fuel pump?
The new timing/water pump and tune kit is done. Today I put in a clean, used MAF (which I had hosed down with CRC MAF cleaner) and Jetronic fuel brain I bought from Ducman82. The mechanic checked the fuel lines before and said they looked fine.
The car turns over well now and runs smoothly at idle. The last timing belt was very old and off time by two teeth. Seems like I'm getting okay spark. It *sounds* great. But no power is coming out.
Any ideas?
Could relays or the temp II sensor cause this? Fuel pump?
#45
Drifting