So I have an opportunity to acquire these and am wondering what the forums thoughts are on using these on the 1995 U.S. models? I did a quick search on here but nothing recent or really informative.

 

They seem to be made for all the later CAN based stuff. The i930 works pretty good but can’t write and program keys/other modules on the newer cars which is why the bootleg mongoose cable is so common.

On the 300 as far as I know even the real old stuff like the WDS on wheels aren’t perfect at reading all the modules. The PDU should be able to diagnose everything but there’s like 5 people in the world with a working one.

 

LOL on a working PDU! I have in previous posts mentioned my using my Snap-On MODIS by using the Lincoln Town Car parameters with some success. According to what several sellers of it say it will work but as to what I have yet to hear any definitive answers. I emailed Icarsoft tech support for more information but have yet to get a reply and no answer when I call.

 

I’ve had good results with OBD Fusion. As long as you only want to see fuel trim, o2, maf and engine codes.

I believe if you want all modules then the only thing would be this https://www.ebay.co.uk/itm/174429204756

too expensive for me!!

 

You can try the mongoose pro JLR or the DA dongle and run an early version of SDD. I have a knockoff cable on the way.

People sell working original Rotunda VCM (1) for about 200 usually, those work with both SDD and IDS. There used to be super high quality fakes for about the same price but unfortunately they’re no longer being made.

 

Really? I thought the X300 1995 wouldn’t work with the Mongoose cable?

 

it should...i’m gonna find out soon

 

Please come back and let us know. What is your setup? Where did you get the cable and what platform/software are you using? Finding the obd fusion useful but I know I will need to look at other modules in the future.

 

Also for those who have the OBD fusion - do you know what this means? Why 2 ECUs? Whichever I select it seems to give similar info.





Plus does resetting the codes also reset the long term fuel trim? I thought it should but mine still reads 50%!!

Any ideas?

 

No. Resetting codes will NOT reset fuel trims. As far as I know, ONLY the PDU can reset long term fuel trims, however that's just a running average of the short term fuel trims and does not affect how the engine fuels the car in any way. It's simply a way to zero out that average to help figure out if you've solved an over/underfuelling issue.

As for the ECUs, I believe it is asking you between ECU and Transmission ECU. When I have some time, I might be able to research this further.

 

Okay thanks for confirming. So should I worry about such a high LTFT when the short term is good?

 

Well, a high LTFT indicates that your STFT is NOT good, or that you have not driven long enough for the LTFT to lower itself, which it will after a week of steady driving. I used to put on about 50 miles a day, and after a week, I would see the LTFT start to come down after I completed a fix.

Remember, all the LTFT is, is a running equation where it continues to save the STFT over a period of time/miles, which it uses to average to give you the LTFT. Resetting it does not affect anything mechanically, electrically, etc. If you were to reset it, you would simply have to wait for the car to average back up to where it was before, assuming you made to fixes to the fueling of the engine.

What is your LTFT at?

 

Okay thanks for the explanation. So LTFT is for reference and has no influence on the ECU.

I have an intermittent stumble when at idle and warmed up. a “miss” every 3-6 seconds. More noticeable in drive but also in park.

here are my stats from OBD Fusion. Tried the smoke test with a cigar in the valve cover breather and a glove over the intake. No discernible leaks.

I have a spark tester like this and all the coils seem rather weak but consistent. I bought a new coil for £30 by Lucas because one of them was cracked at the base and this had the same spark so I assume this is normal for the X300? My Audi 2.8 1998 is MUCH stronger.

I have seen coils for up to £150 EACH so I have to buy 6 of them?? I’d rather diagnose it first before investing if necessary.

help much appreciated!

Spark tester

Stats from OBD Fusion

 

I had a dip at idle every 32 seconds. It ended up being the intake manifold gasket that was leaking. It took 3 shops, including two Jag Specialists to find it! I did cigar tests as well, couldn’t see it. It might be your problem too.

Amazon sells a set of 6 coils that have had very good long term results here on the forum. They are QYL brand. They are $80 for all six.

The STFT must be graphed to see what it’s doing, as it should be constantly changing, like your oxygen sensors do. When was the last time those were changed?

There’s not much else I can diagnose from your screenshots.

Lastly, yes, the LTFT does not affect your engine at all. Resetting it with a PDU would not change the way your engine performs in any way.

 

Okay thanks for your comments. Those coils don’t seem to be available in the UK.

will check the intake manifold. Apart from visual inspection, what else can I do to test it?

Someone else has suggested wrapping tape around the end of the coils so I will try that next.

the other option is injector problems. How can I test spray pattern and flow rate?

 

That's unfortunate, from a pricing standpoint.

I don't know why it took three shops to identify the intake gasket. It's a metal gasket, so perhaps it needs to be tested when the engine is hot, I don't know. If you do end up replacing it, make sure you replace the ******* hose while you're in there. (EAC3454)

You can try the tape. If they're that far off, you may as well swap them all out. The other five are probably originals? Not sure how many miles, but at least 25 years old now?

If you want to pull the injectors, best to just pay someone to do a thorough ultrasonic clean, although you can do it yourself as well, perhaps not as thorough, but posters here have had good results. Search the forums and you'll find some info how to do it. You'll need some rubber hose that connects to the injectors, some hose clamps, some chemical that will clean out the injectors, a 9v battery and a button, so that you can actuate the injector in short bursts so that you don't burn anything out.