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Discussion Starter · #1 ·
Hey ho peoples, my car is currently off the road due to it being a bitch. More to come and many questions to ask if I can't get it sorted!! So apologies for that in advance!

ANYWAY, here's today's (hopefully only) question: I was cleaning the throttle body out yesterday (It wasn't actually that bad at all) due to me having to install a new TPS and connector. Anyway, I noticed that when it was all disconnected, the butterfly plate moves a teeny tiny amount side to side unless I press on the bit that the TPS goes on to. Is this normal? It still does it with the TPS on, by the way.

I'm asking because I'm having a problem with the car running rough as fook and the throttle body sounding like it's constantly open a little. It was worse before I cleaned it - a constant woooosh, which after a few seconds got louder, but now it's more of a constant shhhhhhhhhh. There are no vacuum leaks that I can find (I did the carb cleaner trick) so I'm at a bit of a loss and before I smash the thing up, I was wondering if you guys could help!

For those of you who don't know, it's a 1994 3.4 Auto.

Cheers guys and sorry for the long post!
 

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Did you spray carb cleaner around the bushing area that throttle shaft runs in? Seeing your car is 21 years old,It's a common problem going back to carburetor days for the seals around the bushings to leak air into tb. This not only can cause air sound but also messes with the air/fuel mixture because the extra air is unaccounted for.

And welcome to the forum from across the pond.

What you need is a scan program that can not only read codes but can perform running sensor data scans. Sensor data can point you in the right direction. The program is called "scan9495" There's a version of it made for v-6 cars. Our member GaryDoug wrote the program and he can help you with it, if needed.

Did I mention, the program is free. The only better obd 1 scan tool I know of is the GM tech 2. But it's costly.

You will need a 12 pin obd 1 dlc to usb port cable. And scan9495 only runs on pc based computers.

You will probably have to order the obd 1 12 pin cable from the US. I imagine shipping will be a lot more to UK. But you can get these athttp://www.reddevilriver.com

or http://www.tunercat.com

Also do a google search, you may get lucky and find one in the UK. Forgot to mention eariler, you can have codes and not have the check engine light come on.

And I'm assuming you have the American version of car. UK import version would be right hand drive and probably conform to UK pollution standards.
 

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Discussion Starter · #3 ·
Hey Sea Dog,

Thanks for that and the welcome!

I'll look into the codes and scanner - problem being is that it's that stupid obd 1.5 connector GM used for this year! I sprayed the carb cleaner around the throttle body seal itself and there was no change. I did replace the gaskets less than a year ago, so I wouldn't have thought it to be that. One thing to add is that I found that my 3 pin/2 wire connector on my ignition control module had corroded wires, so I cut them down and popped them back in thinking this would help - it didn't! It's the crank position sensor connector with the twisted wires.

I've taken a video I'm just uploading to you tube, so I'll put that here in a sec, too. You can hear the woooshh in the intake and how rough she's running. You can also her how much of a delay there is when I open the throttle. Also, after the video was shot, I revved slowly and the car just stalled on me.

Here's the video. Please excuse the tape, I'm in the process of cleaning it all up!

 

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If your car has the obd 1 dlc connector with 16 pins instead of the usual 12, it's no problem. The obd1 cable comes in both 12 and 16 pin versions.

My 95 car uses the 16 pin obd1 cable. Scan9495 has no problem reading the pcm.

But your 94 with a 16 pin dlc is unusual. All 94's I've seen use the 12 pin obd1 dlc.

And don't forget the basics. Get a fuel pressure tester and make sure you have around 43 psi at key on prime. When idling pressure can fall to mid 30's. Other running conditions will have higher pressure than idle.

Make sure ignition system is up to par. A spark plug or 2 not firing or with a weak spark can also affect running.
 

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Discussion Starter · #5 ·
So..I managed to work out that the hissing is the IAC valve taking it's time to close up, so that's not too much of a problem. The missing problem still persists though. I tested voltage and resistance to my 3x sensor cable and ignition control module and they all seem fine. The car is constantly missing and has NO power at all. I unplugged injectors to cylinders 2 and 4 and there was no change to the running - so that suggests it's those two it's missing from, right?
 

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I'd say yes, when you unplug the injector for a cylinder the rpm should drop if that cylinder was firing normally.
 

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Ramblin' Wreck
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Were you able to check number 6? Injectors 2, 4, and 6 are on the same circuit with it's own fuse separate from 1, 3, and 5.
 

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Discussion Starter · #8 ·
Oh, I'll look into that, thanks. I only took 2,4 and 1 off as they are easy to get to. Taking number 1 off made the car run even worse, so I know that was OK.
 
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