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Began mods on 954, and now for the problems

rah1482

Well-known member
Joined
Mar 8, 2006
Messages
119
Location
Philippines
Pretty much wanted to maintain 954 bone stock, no mods, just like it came out of the showroom.Partly because of wanting to have an all original VR4 but mostly avoiding the "plague" that upgrades bring...but modifying it was just too hard to resist.

So I proceed with replacing the stock exhaust system with 3 inch pipes, starting from the downpipe all the way to the muffler. At first, I enjoyed the engine being able to breathe and the additional power it brought. Told myself, i should have done this sooner. But that was all till the "check engine" lit up,the anti-lock indicator flashed and the idling became unstable. WTF! I knew it, I shouldn't have touched the sh*t!

Needless to say, I need help! What's going on? I tried to re-set the computer but the symptoms are still coming out.
 

1990ggsxnj

Well-known member
Joined
Nov 21, 2008
Messages
525
Location
Blackwood, NJ
logger logger! Also, could be alternator so check it.
 

BoostedAWD91

Well-known member
Joined
Mar 1, 2007
Messages
2,937
Location
Danville,Pa
make sure the o2 sensor harness is plugged in and the harness isnt messed up or wires coming out of it. This could be the cause of the chk engine light. the idle problem is your IAC(ISC) which probably went bad. Test it and if its no good, you can get a replacement fairly cheap from someone on here. As far as the ABS, these cars ABS systems are not to great and tend to have problems so most people either just disconnect it or remove it completly. I would first find out what codes you have that caused the lights
 

Sounds like a bad alternator to me, which is nothing unusual on these cars, although I'm still using the alternator that came on my car when I bought it over 9 years ago, which I believe to be the original. If you've been driving the car with an impaired alternator, the battery could also be damaged so be sure to have that load tested as well, and it wouldn't hurt to replace it at the same time as the alternator (a bad batter will kill a good alternator and vice versa; I've seen people constantly replacing one then the other because they're too cheap to do both at once...)

And yes the ABS systems do suck, but that doesn't sound like your problem to me. And if you do want to keep it stock, and the ABS craps out on you later, you can just pull the fuse to disable it. Fully removing it, like I'm in the middle of doing, is somewhat labor intensive.
 

rah1482

Well-known member
Joined
Mar 8, 2006
Messages
119
Location
Philippines
Thanks for the diagnosis, guys. The issue really is that it all happened within hours after I picked-up the car from the pipe shop. Before that, car was running fine. Alternator was re-conditioned only 1,000 miles back and brought upto 120 amps. The flashing of the anti-lock, alongside the ticking of the computer is a big worry as it might cause damage to the computer.

Anyways, I will zero-in on the O2 and look up the ISC and the alternator as well.

Anything else? Do I need to re-flash the ECU when I come from stock to 3-inch pipes?
 

Hertz

Staff member
Joined
Jul 29, 2002
Messages
13,501
Location
Chicago, IL
If there is a leak between the o2 housing and the downpipe it can blow hot gas onto the alternator. They don't survive that very long. The voltage regulator is very sensitive to temperature.
 

rah1482

Well-known member
Joined
Mar 8, 2006
Messages
119
Location
Philippines
Thanks Hertz. Your comments make sense and puts the correlation of the new pipes with regard to the conditions being experienced (i.e. alternator, check engine, etc.)

Shall proceed to the pipe shop to check.
 
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