Car starts, revs to 3000 rpm then dies

[91TsiTalon]

Hey guys,

I am in desperate need of some help. My car has been having issues for the past couple weeks and finally it broke down completely.

The car will start up, rev to 3000rpm then go back down to idle and die. I have checked and replaced the EGR and the ISC.

Also i tried to do a boost leak test and it didnt seem like it was doing anything. Can someone please explain to me how to do it? Everywhere I have looked it says "Pull off intake pipe, hook-up boost leak tester and pump it to normal boost levels and spray around known areas for leaks" I did this and my boost gauge registers nothing, as if Im not even putting air in the system. By the way, I put the tester on the turbo.

Sorry for the long post and I know Im gonna feel really stupid when I find out its something really easy.

Thanks and any help is appreciated!

-Daniel

 

[kenamond]

If the motor happens to be "just wrong", the intake and exhaust valves will overlap (both be open on a cylinder), and your boost leak test air will go straight out the tailpipe. You can crank the motor over with a breaker bar and 1/2" drive extension or 22mm socket to get it away from this overlap spot (pull the front-left wheel off to get at the crank pulley). Or you can turn the key on the motor for a fraction of a second and hope the motor stops in a non-overlapped configuration. But if someone listens at the tailpipe and doesn't hear the air hissing out when you apply pressure, it might be a (bad) boost leak.

If it doesn't register on your boost gauge and valve overlap isn't a problem, you have a major leak. First, look at all of the couplers from the turbo to the TB elbow and make sure they're all secure and that a tennis-ball-sized rock didn't go through your intercooler. Then divide and conquer. Disconnect the UICP at the TB elbow and boost leak test at the elbow. Then back up to the intercooler inlet, until you're back at the compressor inlet. Soapy spray bottle only works for small leaks, listening works for medium sized leaks, and visual inspection works for blown couplers or destroyed intercoolers.

And are you using an air compressor or portable compressed air tank? A bike pump will not work.

And you have to have an aftermarket boost gauge. The stock one doesn't actually measure boost pressure and will not work.

 

[91TsiTalon]

Thank you for responding!

I am using an air compressor and yes it is an aftermarket mechanical boost gauge.

 

[truwarrior]

I had the same issue on my 99 GST tonight. I tried starting it 3 times and it kept dieing. I kept the revs about 1000-2000 to make it home and when I got home for further testing it was working perfectly fine again. Ever figure out what your issue was?

 

[kenamond]

I had the same issue on my 99 GST tonight. I tried starting it 3 times and it kept dieing. I kept the revs about 1000-2000 to make it home and when I got home for further testing it was working perfectly fine again. Ever figure out what your issue was?

Is the CEL on? If so, get it read. My car did that once...it wouldn't start or would barely run, then it'd work fine. Initially, it didn't throw a code, but eventually it did...CAS was bad. They're not cheap (~$80), so don't run out and buy one, because it could be something else. Before it threw the code, I was wiggling wires and happened to wiggle the CAS plug and after all the wiggling, the car miraculously started (so I didn't know which wiggle, if any, did the trick). After I read the code, I was able to wiggle the plug anytime it wouldn't start up and it'd start (I drove the car like that for the week waiting on a CAS to ship and learning how to change it...2ga and 2gb CAS are completely different, and the Haynes manual only mentioned the 2ga...which is a PITA to change and which contradicted posts on the forum...which confused me ). On our cars, it's a 1 minute swap...no shit.

But it might be something else...try wiggling the plug next time it happens. It's on the back of the CAS housing which is on the end (passenger side) of the intake cam...unless you have a 2ga CAS for some reason...then it's hidden under the intake cam gear.

 

[vancitydsm]

can you keep it alive with throttle action or will it auto die?

 

[truwarrior]

Thanks for the feedback. This weekend I put my 2G dual piston calipers on and replaced the spark plugs wires with Taylor wires. Everything was working fine until I was pulling into a steep drive way, I got about half way up and slipped the clutch a little to get a tad more up the hill and the RPMs just dropped and the engine died. I know I didn't kill the engine by bogging it.

I started it up again, RPMs went to 3000 RPM fell to 800 then just died. Did this for 3 starts. On the fourth attempts I could free rev the engine all day if I wanted to but then when I let the RPMs drop it immediatly shut off.

When leaving I keep the RPMs up above 1500-2000 and all was well when I got home. I just wiggled all the wires that I could find in the engine bay and everything is ok. A/F ratio is good. Fuel pump sounds strong, etc.

I think it maybe the CAS too but not sure. Any other symptoms of a bad CAS?

 

[kenamond]

When my CAS was acting up, it'd start, rev to 2-3k, sputter, die. I could barely keep it running with the throttle, but not more than a few seconds. Black (rich) smoke out the exhaust or strong gas smell in the exhaust. That's all it did...or it would work perfectly. Like I said, it didn't throw a code for a couple of days, and I had the problem two or three times before it threw the code. I think the ECU has to be in a certain state before it'll throw a code, but I forget what I read about that.

Try wiggling the CAS plug if it happens again. Aside from the cost, it's one of the easiest things to replace on the car. Remove one 10mm bolt, pull it out, unplug it, plug the new one in, lube up the o-ring, pop it in, put the bolt back in. And it's easy to reach. One minute if you hurry.

 

[Jordanbutter]

+1 When my Cam Angle Sensor went out, It would drive, die, start, die, sit over night, start drive 10 miles, die. Its really hard to predict but thats what it sounds like to me. They go out all time, atleast I see these kinda problem posts all the time.

 

[vancitydsm]

Wow i was leaning closer to Idler motor. That is strange how you can keep it alive while working the throttle but dies on idle, that seems unorthodox of a cam sensor to me. But kenamond i think you mean a soft code and hard code. Soft code is pretty much a pending code that the computer might toss up as a hard code which is what sets your engine light. If your cam sensor doesn't act up enough during consecutive drive cycles or on the same drive cycle then it wont set it as a hard code. I'm not too sure though.

 

[silverbullett]

So I just had the same problem tonight. Driving on the freeway it felt like it hit fuel cut, no more power. Coasted it onto the shoulder. Started it and it just died. Tried again with the pedal to the floor. Won't rev past 3k. It won't even hold 3k, it just bounces up and down from 1.5k to 3k at WOT. Completely undrivable. I just had the car towed over to FFTEC so, I guess I'll just have to wait until tomorrow to find out what's wrong. Wish me luck and keep me in your prayers. On a good note though, the car was perfectly drivable for 9 minutes.

 

[eric62810]

IF IT TURNS out to be a cas i actually have one from a 93 7 bolt does not have the harness that comes off but has the plug on it instead i dont know if itlll work for u but i am willing to sell cheaper than 80 the numbers read t1t49571n ox25 its in good working order and if u would like to get message me and we can go from there

 

[silverbullett]

Turns out I blew a coupler on my lower piping . I feel like such a jackass. Sean at FFTEC is taking care of it as I write this. Glad it was just something simple.

 

[truwarrior]

Ya a coupler is a easy one, I boosted tested not long ago and it's fine. Mine wasn't chuggin like a IC pipe issue would. I just started ok, then completely shut of when the rmps got to aroudn 1Kish.