Codes P0101, P0243

jpb2222 · Post by **jpb2222** » 29 Jun 2022, 13:37

Presenting to the Volvo Emergency Room ...

This isn't really an emergency. I've been driving her like this for 2 thousand miles. But it's a sizeable problem that I'll need to fix very quickly.

Here are the codes and their descriptions:
P0243: Turbocharger Wastegate Solenoid A
P0101: Mass Air Flow A Circuit Range / Performance

The symptoms are as follows:
The turbo will not spool in the 4th gear (not sure on this description). What I mean by this is that, while driving above 60mph, I cannot get the car to rev above 3k rpms. If I 'give her the beans' while in this range (60-70mph), either the RPMS will refuse to go above 3k rpms, or the car will *try* to boost and then go into limp mode. This will happen especially if I gas it from 60mph trying to zoom quickly ahead. For now I will creep up the gas in order to inch near 3k rpms. Top speed has been around 75mph on a flat road, 80mph on downhill. Very low power when going uphill.

The turbo is not functioning as it should, in short. Now, the code P0101 hints that the MAF is not functioning correctly; but the vacuum lines to the Turbo solenoid are also very crusty and likely in need of replacement; I have not followed them down to the turbo, but from their condition at the solenoid I imagine they're not in any better condition down yonder.

Has anyone had these 2 codes simultaneously before? I'm weary to shelling out cash for a new MAF and not fixing the problem.
I have an extra MAF I picked up from a salveage yard off an S70 non turbo; does anybody know if the non-turbo MAF's and turbo MAF's are compatible?
What size are the vacuum lines for the turbo solenoid?
How to test the MAF sensor and turbo solenoid?

Cheers
Justin

Post by **scot850** » 29 Jun 2022, 14:45

Hi Justin well that sucks!

Firstly have you tried disconnecting the MAF and driving the car and seeing if the car runs any better? That would at least confirm if the MAF is an issue.

I believe the turbo and non-turbos use the same MAF. There should be a Bosch part number on the MAF, can't recall what it is off the top of my head but you can compare, but I am fairly certain they are the same. I think the 2000 'R' I have is the only one that is different on 98's. 99 on use Denso MAF's on the NA motors which are different.

The Turbo solenoids do fail. Not a common issue but it can happen which will restrict spooling up of the turbo. A junk yard part is the way to go on that as it is easy to swap out. It should be mounted on the side of the air filter box between the box and the distributor.

Neil.

jpb2222 · Post by **jpb2222** » 29 Jun 2022, 17:16

I've disconnected the MAF without change, although I didn't try driving it up to highway speeds.
Looked for a turbo solenoid earlier, but the yard near me had no turbo'd P80s.

I picked up some 1/4in vacuum line earlier today. I will attempt to change out the 3 vacuum lines off the TCV and pick up a T20 security bit to switch out the MAFs.

I'll update this thread when I do with results.

Cheers

Post by **scot850** » 29 Jun 2022, 18:55

You can just remove the whole MAF body saving on the money for a tool (but then who doesn't need more tools!).

The TCV is the easier thing to swap out.

Hopefully the 1/4" pipe works as it is probably a metric bore in the tube like 6 or 7mm.

There is a diaphragm in the turbo wastegate that will fail with age as well. If the other 2 issues don't fix it then that is where I would go next.

I would also carefully go over all the turbo pipework and check for loose pipes, tears and splits.

Neil.

Post by **Chuck W** » 30 Jun 2022, 10:47

Have you tried cleaning the MAF? (With MAF cleaner).

When was the last time the air filter was replaced? How dusty are the roads where you live?

We've had similar issues on the wife's '97 GLT. The TCS and hoses are all new, etc. She had it flake out on her, similar to your issues. I hosed the MAF down with the cleaner and it's been fine since.

The air filter was a bit old, and she makes several trips out to the rural area where her family lives with dusty gravel roads.

The cleaner is worth a shot if the vac hose replacement doesn't help.

Post by **Goupil** » 30 Jun 2022, 13:04

I too went to get Torx security bits for the MAF until I realized it's a 5 point star ! Ended up making a slot with a dremel

Post by **scot850** » 30 Jun 2022, 13:15

Clearly different to a 98 V70 I worked on recently. I removed it with a Torx security bit and refitted it. T20? I think.

Neil.

Post by **abscate** » 30 Jun 2022, 13:24

A Dremel will turn any fastener into a Torx.....

jpb2222 · Post by **jpb2222** » 30 Jun 2022, 18:32

Today:

Looked at the fasteners on the MAF from the V70 and the MAF I picked up from the junkyard S70. Both '98. The MAF on the V70 has security torx T20 fasteners, while the MAF from the S70 has a Torx "PLUS" T20. Two different bits will be required.
Pictures:

: torx.jpg (124.23 KiB) Viewed 793 times

I then replaced the 3 hoses from the TCV. Sort of a PITA. While on the car I checked out the Turbo air hoses, and noticed a hose on the bottom of the car had a very broken clamp. I replaced it, but need to get back out there again and slide the hose further into place. The hoses did not appear to be broken but they were very hard at the ends and crusty.

Further, while replacing the yellow line (which travels to beside the turbo intake), I noticed while taking off the intake that its hose clamp was loose. That may have been causing my problem! So I made sure to tighten it when putting everything back together.
However-- and a big however-- while taking out the intake, I accidentally popped the vacuum line with the square head off of the intake. Busted.
Photo:

: intakehosefailure.jpg (175.35 KiB) Viewed 793 times

I could not get it to fit tightly again, and there was no way of sealing it again with electrical tape. Does anyone know if this piece is meant to be removable? I thought I could squeeze it in there again, but I could not get it to. I am further unsure of the 2 secondary hoses which attach near the square hole. There is one with an elbow and a straight one which comes from the front of the engine.

Does the hose with the elbow attach to the intake or to the nipple on the hose?
I attached it to the nipple on the hose, and the straight hose to the intake nipple.

Anyways, I started her up without regard to the new probable leak I had created, and I had no codes anymore.
I thought, maybe it was a result of disconnecting the battery? Although I had disconnected the battery many times before and the codes remained when I reconnected.
The car idles lower in drive now; while coasting, RPMs appear to be now lower. The car seems slightly more responsive.
I can go above 3k RPMs under 4th gear as before and hear the turbo spool as before, though possibly with more power (I figure this may be placebo).
However, the problem of being unable to go above 3k RPMs in fourth gear persists. I pushed the gas pedal to the floor on the highway, and I was limited to 3k RPMs. But no codes and no sudden spooling/limp mode, and no codes appeared.
So now I am quite confused.
What could be limiting my boost and RPMs above 4th gear? Same vacuum leak?
And again, is that square vacuum line meant to be detachable?

I plan on trying the extra MAF sometime this weekend.

Cheers everybody and happy Friday.

Justin

Post by **rguzz** » 01 Jul 2022, 12:58

ACDelco-214-474-Equipment-Turbocharger-Wastegate/dp/B000EQPBHM on Amazon worked great for me, 96 850T. Get the proper connector that is also listed as well. If vaccuum lines are good everywhere (suspect for sure) make sure the wastegate is properly adjusted search around for procedure for this. I replaced mine with a Chinese one works great.