1990 Laser RS Turbo HELP! Just bought

[RandomZ90]

Ok so I skimmed through some topics and couldn't find anything so heres the deal.
I just bought a RUNNING 1990 Laser RS turbo for $400. It runs great just the only thing is it seems like the idle air control valve is acting up some. Also it is fuel cutting if I get into her past 3/4 throttle or so. Any idea what this could be? It's causing it to smoke ( gas ). Also how can I determine if i is 1g or 2g? Sorry if I seem like a noob it's cause I am. I"m new to the whole turbo ordeal never owned a turboed car or tried it.

Thanks!

-Corey

 

[DSM1G90]

Welcome, and stick around - you might learn something around here.

You got a 1G vehicle, like mine.

You just got it, do you know of what the previous owner did with it as for maintenance?

How do you know about the IAC acting up if you say that you're a newbie?

3/4 throttle open then cutting out could be a fuel filter needs changed, or other things that could be wrong with it.

Smoking could be running rich (black smoke) meaning timing/fuel issues.

White smoke would be a blown turbo that needs rebuilt or replaced.

You got a good deal for $400.oo bucks. Now, more will have to be put into it and we need more detail on what's happening before we can help you out.

(On a side note, I'm now curious on how old your Laser is: look at the manufacturer's sticker which is located on the driver's door "C" pillar and you will see the month and year manufactured located on the upper right of the sticker. ..thx)

Good luck-DSM

 

[RandomZ90]

I'm a noob to turbo systems not cars in general . I am decently good with cars just never had the oportunity to mess with turbo systems. As far as the IAC it revs to 1,300 and then back down to idle rpms ( 700 or so ). does it a few times then stops and sometimes it continues.
Previous owner gave me all papers since he has owned it in 94. It has been well maintained with 174k miles on it.
It is a 89 make ( concidered 90 ) This much I do know it was made in november of 1989.
The main symptoms are when at take off from idle it smoke a little and it smells of gas bad.Also If I floor it , it seems to be fuel cutting , at around 9 to 10lbs of boost. There is a greddy blow of valve and a manual boost controller on it, which it is turned all the way down. Also I do know this that it is leaking on top of the turbo where some washers have worn out ( we are fixing this problem tomorrow it's leaking some ). But he said it wouldn't affect the fuel cut , he thinks it could be a leak in the system somewhere.

 

[Dhan]

That idle oscillation you're describing is what we call idle surge or fast idle. There is a problem with the air/fuel mixture and the ecu is trying to compensate.

Here's a good resource on it as well as how to fix it Terry's Talon Troubleshooting Tips #3 - Fast Idle (aka. Idle Surge)

 

[RandomZ90]

It isn't stalling though, It's acting as if the plunger in the IAC is sticking.

 

[DSM1G90]

(I'm a June of 1989..)

Have you tried to reset the plunger in the IAC?

There is a FAQ in this site VFAQ Site - Visual Frequently Answered Questions on how to adjust the IAC to meet the BISS screw adjustment to settle that oscillating idle down.

But first, make sure that the t-cable has enough slack before doing any of this adjustment ..about an 1/8" slack in the cable with throttle plate fully closed.

And changing out IAC units if the coils are shot is a PITA with our '90's since the IAC sits at a right angle to the T-body instead of the 91's when they got smart and mounted the IAC units inline with the T-body. You have to take out the T-body to do the IAC changeout in our '90 units.

Good luck-DSM

 

[RandomZ90]

I've owned the car for 3 hours now . I'll have to check it tomorrow. Early when I did a quit run through It seemed the cable was tight enough. I'm thinking just the age that it might have some build up. It might be able to get cleaned.Friday it's making a 200mile trip back home . I'm going to school right now and bought it down here, I"m taking it back home to get tagged etc then I'm bringing it back down here. My main concern right now though is the fuel cutting. The IAC is a easy fix. Just that fuel cutting is a wee annoying.

 

[907gs-t]

Welcome to DSM Tuners.

 

[boostin_93]

I bought my talon for 1500 3rd one in 7 years this one i will keep flawless body but a week after i bought it i get rattling cutting out spend close to a grand to get it running great point being my friend is 400 bucks not bad spend 500-1000 to fix everything and run a dying breed.....priceless......

 

[DSM1G90]

( where's the punctuation and caps? that was a well run-together quote above - now, let's see if you can read it back to us...)

..a 21yr old dying breed that some of us have. But, parts are still a-plenty to have to keep these "road dinosaurs" alive and kicking through the next generation...until someone wants to run into you and end that dream that you have.

 

[jimbob_843]

You say the turbo is leaking on the exhaust mani? This will cause you to cut out. Also do a boost leak test and always remember maintance first! Welcome to tuners

Recirc that bov, remove mbc, boost leak test, fix exhaust leak

 

[RandomZ90]

ah that is what I was thinking, and I'm down here in Nashville for school so I have no one to really help me. My bestfriend back home is good with it. I have no choice though but to drive it 200 miles tomorrow back home. You think it will be ok?