Engine Running Rough

pete_gpx · Post by **pete_gpx** » Sun Sep 28, 2008 12:38 am

Right, so I just got my 96 Tiptronic GPX on the road 2 days ago, I've been driving it heaps and enjoying the hell out of it. It was in the shop for an engine change, which went reasonably smoothly (exchanged a 217 000k engine for a 147 000k one that wasn't burning oil).

So my problem is this; When I start the car up, it seems to idle ok, sitting at about 900 RPM. When I take it out of park and put it into drive or reverse, the revs drop to about 500, or even as low as 250 sometimes. When it does this, the car shudders and feels like it's very close to stalling, with the lights occasionally dimming. This seems to be worse when it's cold, although I haven't really been driving it long enough to extensively test this.

When driving, the car seems to surge forwards a little while at low speeds. This is a little hard to describe, but when cruising at, say, 40, it will feel like a tiny bit of throttle is being applied and then backed off repeatedly.

I've done a little bit of searching on the forums, and I've come to the conclusion that it could either be my stepper motor or that the car is running rich.

Any help with this would be greatly appreciated.

Despite this, I'm still absolutely loving my FTO.

Post by **I8A4RE** » Sun Sep 28, 2008 8:54 am

It sounds like stepper to me. i would not think it is running to rich by what you have told me. Check ecu error codes as that can identify problems (taking the guess work out of it)

Either give your stepper motor a clean or replace it. what happened to your old engine? did they use the ancillaries of that or did they come with the engine? you may be able to get your old one back.

Personally i would be taking the car back and blamming it on the mechanics. When you pay for an engine swap you are paying for a working one and yours is nott working properly. put it back in their hands

da_msta_chizz · Post by **da_msta_chizz** » Sun Sep 28, 2008 9:44 am

I8A4RE wrote:Personally i would be taking the car back and blamming it on the mechanics. When you pay for an engine swap you are paying for a working one and yours is nott working properly. put it back in their hands

+1.

They should have tested it before giving it back to you..

pete_gpx · Post by **pete_gpx** » Sun Sep 28, 2008 11:16 am

I bought the engine from a wreckers down in Brisbane, took it to the mechanics and asked them to do the exchange for me. Although they did test the car out for a few drives and then did a roadworthy on it for me, so yeah, I will be taking it back to them.

With the engine I got everything like alternator, starter motor, torque converter etc. I have the old engine sitting at my parents place in a shed.

Also, one thing I didn't mention, after heavy driving (yes, me driving like an idiot), there's occasionally a very distinct fume-like smell. I had already asked the mechanics about this, and they claimed there was a bit of oil etc. on the engine block and that the smell was most likely the residue burning off and would take a few days to go away.

payaya · Post by **payaya** » Fri Oct 03, 2008 3:18 am

Stepper motor, TPS, dirty TB.

pete_gpx · Post by **pete_gpx** » Tue Oct 07, 2008 1:20 am

One thing I've also noticed, is that when the car is idling rough in reverse or drive, whenever the revs fluctuate, so does the voltage metre. Usually it sits at about 13 or so, but can dip as low as 11. Whenever I turn on the heater, turn the wheel to activate the power steering, depress the brake, use the power windows etc. it also dips a little.

Is this normal, since load is being taken from the current? Or should it remain at a constant value and does this problem indicate an alternator/wiring/battery problem?

The alternator has apparently either been replaced or reconditioned with a service about a year ago.

pete_gpx · Post by **pete_gpx** » Thu Oct 09, 2008 9:18 pm

Also, I've identified that the fume smell, definitely fuel, is apparent when the car is first turned on.

From what I've read in a few old threads, I'm beginning to think that it could be my O2 sensor making the engine run a little rich.

I've read that cheap, generic sensors can be used to replace mine if that's what's causing the problem. Can anyone recommend a brand to look for? Or an eBay link to one that would be suitable?

Thanks.

Post by **I8A4RE** » Thu Oct 09, 2008 10:49 pm

check diy section for all info on o2 sensor

RallyMad · Post by **RallyMad** » Fri Oct 10, 2008 11:15 pm

pete_gpx, I used to get this a bit and I've found a bottle of injector cleaner every now and then does the trick. My o2 sensor has been checked and is fine so I know it's just injectors. Run a bottle through next time you fill up and see how you go.

pete_gpx · Post by **pete_gpx** » Mon Oct 20, 2008 12:53 am

I tried a bottle of injector cleaner, and while the car seems to be running better over all, the problem is still not completely gone. I'm thinking of replacing my O2 sensor, under the advice of a few friends.

pete_gpx · Post by **pete_gpx** » Mon Oct 20, 2008 1:27 am

Would this oxygen sensor be suitable?

http://cgi.ebay.com/ebaymotors/O2-OXYGE ... enameZWDVW

pete_gpx · Post by **pete_gpx** » Tue Oct 21, 2008 2:29 pm

Sorry to bump this so many times, but I'm really keen to get this fixed. Would the sensor in the link above be suitable?

Post by **I8A4RE** » Tue Oct 21, 2008 2:50 pm

Hey mate give these guys a call. I brought his last 2 form him but that was 6 months ago so he should have some more in stock. About $60 fitted perfectly and i fitted mine over a year ago and works sweet as

Hi-Flow
1800 817 006

Ask for universal 4 wire

pete_gpx · Post by **pete_gpx** » Thu Oct 23, 2008 12:57 am

Would the eBay one I mentioned/other ones on eBay be suitable? I read that a Galant sensor is a straight fit.

Post by **I8A4RE** » Thu Oct 23, 2008 8:10 am

I dont know mate, it probably would fit but whats the point in taking the risk? To save 10-20 bucks? Which it will just ending costing you more if it doesnt.

It says on that ebay link that it fits 4g seris engines but nothing about the 6a. As i say, it probably would fit but the ones from hi-flow definitly will.

nikhan · Post by **nikhan** » Thu Oct 23, 2008 10:47 am

Yupz...I gave them a call. Thay are in Melbourne and it cost 54 bucks not including postage for the universal 4 wire. Probably gonna get one

RallyMad · Post by **RallyMad** » Thu Oct 23, 2008 12:48 pm

Mate, had another idea.

You told me the injector cleaner helped, I had some really bad issues for a while with crap fuel up here. Only put in BP now. The Big w/Caltex at the Range in particular has a bad name, think they use their old leaded tanks for their Vortex 98 which is really not good. Had some interesting tanks of crap from there.

I'd still be changing that o2 sensor but maybe think about changing the fuel filters and a professional injector clean after that if that doesn't finish the issues. I have some cold start issues as well, though I wouldn't call it running rough. I'm going to be replacing my stepper motor some time shortly and if that doesn't fix it I'll be doing the above as well so we might be able to replace the fuel filters at a DIY day if your still interested at that time.

Mind you I can't reccomend enough BP fuel up here. I've that the few dollars extra to fill up are helping me in the long run to not get as much issues.

Post by **I8A4RE** » Thu Oct 23, 2008 7:54 pm

^^^^^^^ couldnt agree more, i only use BP ultimate

payaya · Post by **payaya** » Thu Oct 23, 2008 11:46 pm

payaya wrote:Stepper motor, TPS, dirty TB.

Again Im going to quote what I said previously.

No sh*t you smel fuel when your car first turns on your car has to warm up before it starts working dude.

pete_gpx · Post by **pete_gpx** » Thu Oct 23, 2008 11:57 pm

payaya wrote:
payaya wrote:Stepper motor, TPS, dirty TB.
Again Im going to quote what I said previously.

No sh*t you smel fuel when your car first turns on your car has to warm up before it starts working dude.

I can smell fuel after I've driven the car, not just when I start it up.

I only use BP Ultimate in the FTO, or occasionally Shell V-Power when it's convenient (although I swear I can notice the difference from Ultimate...)

Thanks heaps for that, Simon and Nikhan, I'll give them a call myself within the next week and order one. Hopefully it should sort it out, but if not, the fuel filter and injector cleaning might be the way to go.