weird problem for the pros

J

johnrada

Registered User
I finally got my blower back together and got a belt for the supercharger, Ricardo you were right you do have to jack up the blower a quarter inch with the old belt from the 15% OD kit. Now I was very excited to see the car in action and when I drove the car under part throttle, it acted normal under normal driving conditions. When i had the car at WOT it cuts down on power, stumbles, and the tach temporarily drops. Does anyone know what to check first? My friend and I assumed perhaps the MAF was getting a bad reading or maybe the TPS cannot read the throttle position, but this does not apply to the tach problem at all?:confused: Any ideas?
 
you think so? i replaced it last year :mad: but i know they love to break. that would explain the tach also? that is what's throwing me off the most
 
I've searched and I can't find the paperclip method, does anyone know where that post on the 'how to' is?
 
here you go


KMT said:
Use paperclip where it says jumper...
test.gif

The SC's self-test connector should be over on the
You need to decode the number of times the CEL flashes to interpret the codes.
Click to expand...
 
Awesome information, I could not find the post so thank you very much. I do not believe there is a lack of fuel, but I'm also not dumb enough to just rule out something so I will check on the fuel pressure. Mods are as follows on my member page. The only things I have really had to fix in the past aside from a head gasket job, is that I did replace the DIS and cam sensor last year because of a no start problem. I'll pull the codes tomorrow in between classes and see what I come up with. Has anyone else had these symptoms before? It's very strange it seemed as if 2 days ago it took off all the way to 4 grand before it hiccuped for the first time. In later tests any hard throttle around 2500 rpm it cuts in and out, it bucks and the tach drops, I get out of the throttle and it acts like nothing happened.
 
Mine did this. Turned out that the rubber fuel line in the tank that connects the pump to the metal fuel line had split. At idle, it would show about 40psi, but when you turn the key off, it would drop to near zero. I tought that my pump seals were bad. While it was apart, I put in a walbro pump.
 
johnrada said:
Awesome information, I could not find the post so thank you very much. I do not believe there is a lack of fuel, but I'm also not dumb enough to just rule out something so I will check on the fuel pressure. Mods are as follows on my member page. The only things I have really had to fix in the past aside from a head gasket job, is that I did replace the DIS and cam sensor last year because of a no start problem. I'll pull the codes tomorrow in between classes and see what I come up with. Has anyone else had these symptoms before? It's very strange it seemed as if 2 days ago it took off all the way to 4 grand before it hiccuped for the first time. In later tests any hard throttle around 2500 rpm it cuts in and out, it bucks and the tach drops, I get out of the throttle and it acts like nothing happened.
Click to expand...

Bucking under a load is almost always an ignition problem. Was the car running well before messing with the supercharger ?

David
 
David Neibert said:
Bucking under a load is almost always an ignition problem. Was the car running well before messing with the supercharger ?

David
Click to expand...

Dave is correct make sure all your wires are on I just went through this after a starter replacement I knocked off a wire the car ran "OK" under part throttle but missed bad under load.
 
yes but the only thing i do to the supercharger is raise it a quarter inch and put on a new belt. Most of the ignition to the car is new like i said new cam sensor, new DIS, new coil, new wires, even new plugs last year. I need to wait for a friend to pull codes and for now i'll check all the connections.
 
http://www.sccoa.com/forums/showthread.php?t=105077

Same thing happened to me...I tried replacing the cam and Dis as people suggested, but it didn't help. It ended up that I had a vaccuum leak from the hose that runs from between the MAF and TB over to the drivers side valve cover. Combined with my MAF being out of sync because of a cheap CAI, my car was running lean. Somehow the lean condition caused all my problems...Fixed my vaccuum leak and put my original air intake back on and all has been fine since...I still don't understand why, but somehow the lean condition caused my tach to drop off and the car to buck...
 
just got done pulling codes, though i do have a serious brain malfunction. i was able to make out the 111 for system pass, and the 212 at the end (spout grounded). However, there were 2 that didn't seem to go together in the right sequence, so i had a hard time separating the 2 codes but since there are no single digit codes and there were 4 numbers given, i assume it is 12 RPM not within self-test upper limit, and 13 RPM not within self-test lower limit. so it's pretty much a DIS problem with the 212?
 
Probably a loose wiring connection or the supercharger belt is rubbing against the crank sensor wiring harness. Double check everything you disconnected to adjust the supercharger mounting height. Curious...Does your car have EGR ?

David
 
212 C Loss of TACH input to ECA; SPOUT circuit grounded

...is a stored code, which at least would jive w/the intermittent issues you mentioned.

Check the connector(s) at the DIS to be sure they are clean and making good contact & check the resistance to ground from the DIS - ref. N8 at this link... See this link for pin-outs, etc.

Consider running a temporary ground wire from one of the DIS mounting bolts back to the negative battery terminal for testing.

What is the general health of your engine bay wiring?
 
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no EGR, the wiring is all sealed up aside from an old tear in the wiring harness as you mentioned from the supercharger belt, but i repaired that to brand new so it should be ok. anything else i should check while i'm there? after class i'll test the DIS ground and all the connections
 
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