Poor Running 2000 XC70 linked to the Main Relay- Engine System. . .

[JBMorris]

Hii Folks,
Had a poor running condition that came out of nowhere and no DTC trouble codes found.
[Went to start the car again after having been run and warmed up],Would run [Missing badly]but wouldn't rev past about 2000 rpm, [and had to idle back into home base].

Removed and re-installed the Main relay-(engine system) #9162300.
Car ran perfectly the rest of the day. . .
[Same thing happened a day later (today) and at the same location]

Made an inquiry to IPD and got this response:

That's an odd one. Perhaps by removing the relay you effectively did a hard restart of the ECU, which may have a cleared a stored or pending code.
I'd definitely recommend keeping an eye on it, and potentially getting the vehicle into a good Independent repair shop if it happens again. It sounds as if your car went into a limp home safe mode somehow or another, it's just a matter of figuring out what triggered that.

Have ordered a new relay as the same condition cropped up again today.
So a search on ECU- Re learning came up with 2 scenarios:
1. is to touch the battery cables together. . .
2. is to re-learn the ECU by disconnecting the negative cable only and tap the brake s a few times.
Reconnect cable with key in position II, to avoid problem with triggering an SRS fault.

Should I just replace the new relay dead-nuts or follow a particular procedure before doing so?
[or should I try an ECU Clearing with the existing relay]
Unemployed and can't afford a Dealer visit.



Comments appreciated- car has about 140,000 miles.

Thanks in Advance any and all help. . .
Brien

[3p141592654]

If the car was in limp mode, a code had to have been stored. Do you have access to VIDA so that you can pull out the codes? I wouldn't start throwing parts at it until you know the root cause.

[JBMorris]

If the car was in limp mode, a code had to have been stored. Do you have access to VIDA so that you can pull out the codes? I wouldn't start throwing parts at it until you know the root cause.

Hi - no codes using Actron Auto Scanner. . .
I don't know anything about VIDA but would like to learn. [Vadis- volvo automotive diagnostic information systems]?
You are correct about throwing parts- the new relay still caused a stumble on a cold start.
So far, have cleaned the Mass Airflow Sensor and noticed a possible loose wire clip connection from about a year ago when I replaced the ABS module with a Vic Rocha rebuild.
Even though the MAF looked clean, sprayed it down and used WD40 on the connector, at the moment it's running fine. . .
When I first had the car [used] all service was done by the dealer as I had a job.
Now unemployed and can't afford it.

[JRL]

Vadis is not used anymore, (hasn't for years), the newer system is called VIDA

[3p141592654]

Strange, no codes?? You can buy a clone VIDA on Ebay. Digs out lots of details that a standard scanner won't report.

I once had a weird problem where the battery was weak and the voltage would dip to 7V during cranking. That was enough to reset a bunch of things and cause all sorts of havoc with codes and warning lights. Finally clued in to the problem when it wouldn't pass our smog check due to readiness indicators not completing... at that point I realized the ECU was being reset on a regular basis.
If you can, check your cranking voltage and make sure it stays above 9V at the battery.

[JBMorris]

Had an independent repair shop scan for error codes today using a similar tool to VIDA.
Found 5 codes related to a faulty ETM.
Suggested around $600 to install a used unit. . . doesn't sound too good.

Vic Rocha, who repaired my ABS unit (successfully), quotes $285 to re-build the ETM but states:

There is a recall for the ETM, you must have the recall done before attempting the repair of your ETM.

and:

Even though a software update is not necessary, it is advisable to get the latest software installed on your Volvo, it corrects a few issues that were in need of correction.

XeMODex quotes $499 for a full re-man. with pre loaded software,
or,
$439 for repair and return, no mention of software. . .

So, now there is a dilemma, which is the best avenue for repair without having to bring it to the Dealer?

Help, guidance, advice appreciated. . .

[Edit: The unit is being removed with help from watching the XeMODex video.]
Brien

[JRL]

Used or Xemodex does not require a trip to the dealer
However, you need to be 100% sure that your throttle is the problem or you just be wasting 4-$800.

You said it's running fine so I would just take a wait and see attitude

[JBMorris]

Well, after a lot of research and fingers crossed, went with XeMODex ETM and glad for it.
Ordered it yesterday, got here this AM, and now my Volvo is back and running perfectly. . .
It is plug and play-as advertised- and that alone was a big factor in the decision to try it.

Some tips:
1] use a small mirror to help you see what you cant see.

2] the electrical connections all pull apart with finger pressure points, it helps to color code with paint as you take them apart.

3] the electric fan assembly has to be removed from the plastic shroud but only the top 2 screws need to be removed. the bottom 2 screws only need to be loosened sufficiently for the slotted connections to pull free.

4]there is a plastic tab on the big air intake pipe that, once you get the pipe off, should be trimmed off, this will make reassembly easier.

5] the radiator assembly has a plastic stub up for the coolant recovery tank. remove the hose from this stub as it's prone to breakage when the fan shroud comes off. mine was trimmed after removal to prevent this- my sister has the same car and this stub was broken , then jury-rigged by a previous owner.

6] before assembling the air intake pipe back on- use a piece of foil tape to hold the clamp in a position where you can get at it without the clamp revolving away from you.

7] take off the plastic belly pan from under the front end- will help out when you need to see underneath.

Hope this helps anyone who might tackle this job.

[JRL]

Glad you got it fixed.
You need to learn correct engine terms, "Main Engine Relay"? No such a part with that nomenclature

[JBMorris]

This same relay (#1) was used for Air Conditioning as per some web queries but it is what it is. . .

I don't read French. . .