Very Strange Problem

[ncarnova]

I have a very strange issue with my 98 I-30 )(125K Miles)

First, this problem is intermittent. It does not seem to happen with any particular (understandable) frequency. It just happens once in a while and lasts for as little as an hour and as long as a day In the last 4-5 months it's happened as often as weekly, and as seldom as monthly.

The symptoms are as follows:

1) The car seems to be stuck in second gear, regardless of the speed I am going
2) The gas gauge pegs out just below full, regardless of how much gas I have (I've filled up, and been almost empty, no difference)
3) The temperature gauge pegs out just below H, regardless of the actual temperature

This comes and goes. Nothing actually is wrong with the exception of the problem with it being stuck in one gear.

Is there any logical explanation for this?

If you can help, thank you very much.

ncarnova

[loystock]

Looks like a loose/faulty electrical connection or harness. Refer to the FSM (Factory Service Manual) and go to pages EL-6 and EL-11 and pay a close attention to Fuse #13 (10 Amps), downstream of the Ignition Relay. This fuse supplies power to VSS (Vehicle Speed Sensor) hence the the erratic shifting as well as the METERS, including the Fuel Gauge and Temp Gauge. Refer to pages EL-300 and 301 for location of fuses. Make sure they are seated firmly and the associated wirings are secure.

http://www.nicoclub.com/FSM/i30/1998_I30/el.pdf

[ncarnova]

Thank you, I'll check on this. Not being experienced in electronics, may I ask if Fuse #13 is one of the ones in the Fuse box right above the driver's legs?

Thanks, ncarnova

[loystock]

That's right. But you also have to check the other fuses.

[ncarnova]

An update, I have had the check engine light checked and I am getting the following codes:

P0440 Evaporative Emission Control System Malfunction (this has been around for some time, I suspect I need a canister or a valve)
P0600 Serial Communication Link Malfunction (???)
P0325 Knock Sensor Circuit Malfunction (this was replaced about a year ago after the same code, I suspect it actually is the circuit, or can the ECM cause this??)

I'm wondering which of these are related, and exactly what I need to replace.

Any additional help is appreciated, thanks for your help so far.

[maxhopper]

The P0600 is what's causing your issue. It's either the TCM (transmission control module), ECM (engine control module), or the wiring between the two.

Diagnostics for DTC P0600 can be found starting on page EC-314 of the FSM. http://www.nicoclub.com/FSM/i30/1998_I30/ec.pdf