Many Throttle Issues
 

Hello !
I just joined this forum because I bought a superb volvo s80 in february.

So... Bad things started when the car stalled and an unstable idle, up and down, (1000rpm, 1500rpm then 900... etc) and sometimes it would do it so low, it simply stalled. The stalling got fixed cleaning the Throttle body, awesome, but not the idle issue.
My mechanic dived into it and said that even if the throttle body was clean, it was dying and so were the spark plugs. He replaced the spark plugs and it was... smoother but still not good.
He then replaced the throttle body for a brand new one, original part from Volvo and boy hell unleashed. It had to be reprogrammed and the car ran like absolute garbage. The main dealer reprogrammed the throttle body and ... well.... it's drivable but not quite.

ISSUES RIGHT NOW: The car does two different weird things.
1. The rough idle: touch the throttle, it revs and goes back down to 1000rpm then rises to 1500rpm and back to 1000. It does this about 3-4 times and stabilizes.
2. Touch the throttle and the car starts to rev by itself ! all the way to 4000 then 3500, 3700, 2500 and stabilises... not... not brilliant.

What does my mechanic thinks it might be... he bought a specialized Volvo computer because the ones he had were no good. An error code for the Lambda sonds pop up. Apparently before I bought the car, they got changed and it looks like they didn't do a good job. Since they measure the richness of the fuel/air mixture, those being bad could mean the engine computer is trying to compensate and does not know what to do.

Could it be that? Has anyone had this kind of issues ?

Thanks in advance

I have the same problem. Did you find any solution?

Honestly, that is from a guy who made 2 posts the same day - 4 years ago. I don't think he's going to respond.

His main issue was that he chose his mechanic poorly. The man was not knowledgeable about Volvos and me proceeded to do what they all do - throw parts at it until the owner of the car is broke or sells the car. If you can't figure it out find an independent volvo garage.

You could have one, or more, of many issues, I think I would start with checking every vacuum line and T.

Hi, yes, we found the solution. It was the fault of a combination of many parts. I bought the car cheap and what is cheap usually goes expensive. It was the fuel filter, the lambda sonds which were "OK" according to electronics but inadequate for the car (cheap ones). Also some other sensor that measures air intake. Checking vacuum lines is, of course, a good place to start. Mine were all fine.

After fitting all of these and paid a large bill. The car ran beautifully for many years. I passed it to another owner who needed something reliable and safe for his new family.

As far as I know, the car is still running great as I kept in touch with the new owner.

Hi! Yes, you are right. My trusted mechanic admitted defeat and did not charge me for his labour, only parts. He was at a loss because, after some investigations, I was scammed. The car I bought cheap had hidden issues that were fixed in a hurry. With time those fixes started to fail and it was very difficult to locate the issue.

To be honest, about the Volvo specialist.. I had the car inspected by a Volvo dealership before purchase of the car and they did not even see a massive oil leak, not other electric faults that had been present for quite some time.

I'm my city, when the car started to fail and my mechanic admitted defeat, I had to bring it to the local Volvo specialist... And they too were at a loss and could not guarantee repairs as the "car was very old" and didn't know much about it anymore. I also brought it for another issue about headrest and didn't had a clue and had to fix it myself.

Anyway. As I replied to the other gentleman, the car was eventually fixed and ran faultlessly for years. I eventually sold it off as pollution laws in my country are getting rerrictive and a car that age can't drive in city center anymore. It now provides service to a new family.

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