Lanos in Limp Mode

[uptonmustang]

Hello all. I'm new to the world of Daewoo and unfortunately have to start this relationship with a problem. I found a good buy in my 46,000 ml. 2000 lanos SX 4 door 1.6 DOHC Auto. When I purchased it a few days ago, it had been parked for about 8 months, as the previous owner could not get it to start. Upon purchase, I drained the old fuel, replaced the Battery, Fuel Filter, plugs and wires. The engine would crank fine, but had no spark to the coil pack. I checked over connections to Cam Position Sensor, Crank Positon/ Angle Sensor and when I tried it again, it started up. It runs okay, though a little rough from sitting, understandably. Fuel pressure at the rail is about 46 psi. The problem is that at about half throttle, the engine feels like it hits a rev limiter. It isn't like it's bogging down from a bad cat or lack of fuel/ air. It actually sounds like it hits a limiter. I scanned for codes, and found the TPS had been tripped. I changed that out for $30 and it actually ran worse and shifted harder than anything I've ever felt, even after disconnecting the battery for about 5 min to reset. I put the old one back in, and now it's back to exactly the way it was. It idles fine, and picks up speed fine, so long as I don't put it to the rug. I'm stumped at this point, and am not sure where to turn. Replacing Crank Sensor? Cam Sensor? PCM/ECU? I don't want to throw parts at it if I don't have to. I'll also mention that at random points while driving, it has cut out a few times, but picks back up. Has happened at idle, as well as while driving.

My apologies for my first post being a problem, but until 10 minutes ago, I had no idea this even existed. Thanks to all who make this site possible for illiterates such as myself. Thanks in advance, to any responses.

[MMamdouh]

if it is an auto then it won't rev past 4000 RPM in park

did you clean the idle controller, throttle body and intake mani??

MMamdouh

[Daniel]

Welcome here uptonmustang,

Cant' answer your problem, sorry.
Note that at 46,000ml & 10 years it's time to have the timing kit changed if not already done. This is a interference engine.

Daniel

[uptonmustang]

Yes, it is an auto. and it hits the 4000 limit whether in park or drive. I haven't yet cleaned the above mentioned parts, as I didn't feel that they were a direct cause to this problem. As far as the timing belt, it does appear that it has been replaced fairly recently, based on it's like new condition. As far as my problem goes, I'm still in the dark. Thanks for the response.

[Trey05Woo]

Honestly, sounds like the transmission is slipping to me. If the engine speed rises far more quickly than the signal the tcc is sending, the pcm will recognize this as no load (think neutral or park) and engage the rev limiter.

[uptonmustang]

I'm positive that the trans doesn't slip. It pulls exceptionally well for a four-banger up until it limits. And idea where the park/ neutral switch is located? I've dismantled the center console, but don't see anything other than the brake/ shift lock switch.

[Trey05Woo]

The neutral safety switch has absolutely nothing to do with the rev limiter. This is built into the PCM. The neutral safety switch is located on the transmission itself under the battery. Rereading your post you suspect the timing belt was changed, I would start there. It's might be off timing.

What TPS code did you have? no signal, over voltage, under? The TPS is extremely important in this application since its the only means for the computer to know the amount of air entering the engine. However the description of the code is important because it will tell what is going on with the circuit.

[uptonmustang]

Okay guys, so I figured out my issues. The code that I was pulling was for the TPS Under voltage. Replaced it and that code dissappeared. However, it was still cutting out at 4k rpms, and at random intervals, the engine would cut out and it finally got so that it wouldn't start back up. I started tracing over all of the senor wiring that I could and found that there was a small cut in the boot surrounding the Crank Sensor. It had severed one of the three wires inside the jacket and was making intermittent contact. I replaced the sensor, and now my power is up and my rev limit is back up where it is supposed to be. I'm pleased with the info that I've found on this site and will definitely contribute in the future. Thanks for the replies and hopefully this helps someone else who's having a similair issue.

[Puddle31]

glad you got it all worked out. those intermittent issues will drive you nuts. I am sure you will have other issues and many of them have been solved by the people on this site. it will save you lots of time and aggravation!!