2011 Buick Regal stuck in limp-mode

[92saturnsl2]

I have a buddy looking for an inexpensive car for his wife. He called me about a 2011 Buick Regal turbo 4cyl (192K miles) for sale and was able to talk the guy down to $1,500-- except it has issues. He hasn't committed yet but called me about it.

The history of the car is that it needed an engine replacement, so the mechanic they took it to swapped in a Jasper reman. Ever since, the car has been stuck in "limp-home" mode where it will not, under any condition, go over 3,000 RPM and power is limited. In desperation, the mechanic swapped in a Jasper reman transmission-- this is what the owner has said. Long story short, the mechanic threw his hands up said he can't fix it, and the seller just wants to get rid of it. What he told my buddy is the mechanic is suspicious that the car is a late 2010 build but titled as a 2011 model year, and believes Jasper sent "too new" of an engine, one designed for 2011. Would this make any difference?

I basically told him it's a gamble but I think it's one worth taking-- even if it's a complete basket case, the engine, trans, etc. would be worth that.

I have a bi-directional scan tool, MDI-2 clone, and a Techline Connect / SPS account which I can use to do module programming. Also a big shop with a lift. I'm thinking this is a software issue, or perhaps the ECU needs replaced, but either way I'm well equipped to diagnose it-- I think. Just don't know a lot about these cars, and whether being a late-2010 build makes any difference as it pertains to using a 2011 re-man engine.

 

[cheesepuffs2]

I think that sounds like a nightmare at any cost.

 

[LazyDog]

You can always take it to Ivan!

 

[skyactiv]

I wonder if the cam driven HPFP is out and its only running on the in tank fuel pump?

 

[mrsilv04]

The first mistake here was made when anything touched by Jasper was used. Hard pass.

 

[oldcodger]

Would not touch it with a 10 ft pole. It is one thing to buy a used car with a known problem for which you have an exact fix than to buy one with a wide open ended problem.

 

[92saturnsl2]

I think a lot of posters speak of a time when a running used car cost SPS programming (and what needs to take place when engine is swapped), or knows if there was some change between 2010-2011 models that would cause it to be stuck in limp mode.

I'm only going on hearsay and that's all we have until I can get my hands on it--- IF I get my hands on it. I offered my friend to ride over there after work with him tomorrow with my scan tools, but it's terribly inconvenient and he knows it, so he probably won't take me up on it-- car is 30 miles north of our work, when I live 35 miles south of work.

If he wants to gamble it's on him, but I figured I'd try to gather as much information on the subject as I can.

Car was driving and working 100% before engine died (unknown reason) and the Jasper unit put in. I've seen videos of the car in its current condition (when my friend went for test drive) and it runs / sounds fine, only thing out of the ordinary is traction control and check engine light, and stuck in limp mode which limits RPM to <3000.

 

[SatinSilver]

Maybe @clinebarger has some tips.

 

[hemitom]

I wonder if some electrical connections were damaged on reassembly ?
had some g.m cars that went into limp mode with bad throttle body, one with bad t.p.s sensor.

 

[GSCJR]

Maybe @clinebarger has some tips.

+1 or @14Accent

 

[Malo83]

Pass!

 

[clinebarger]

Scan it for DTC's & report back (Complete scan of all modules)

 

[14Accent]

That thing should have a ton of codes stored. The ECM is limiting throttle control for some reason, you have to find out why.

 

[wtd]

What Clinebarger said. Without scanning it you don't have any direction to go on.

 

[GMBoy]

This is a GOOD gamble as the limp mode (which is now called reduced power) is almost always gonna be electrical. I have experience with these motors and the first suspect is wiring during the engine change. Check all grounds including the one on the head, check for damaged wires and for bent pins at every connection. I am amazed this mechanic "threw" a new trans at this. They do have issues with throttle bodies as well. I think with the tools you have you will see the issue and fix it quickly - and make out well.

 

[92saturnsl2]

So my buddy ended up buying the car. Will probably be a week or more before I see it.



- This is a video of the car running in the seller's driveway, my friend reports that it drives down the road just fine but struggles to maintain 40+ mph- not because an engine issue but the ECU cutting power. The only thing that got my attention in the video was the absence of turbo noise, but I suspect the ECU is just dumping boost.

Hard to take a seller's word at face value when they're trying to dump a non-working car-- seller might have mentioned the mechanic throwing a transmission at it just to sweeten the deal, I can't be sure. But my friend is knowledgeable enough to inspect it thoroughly and discern the difference between a transmission in use for nearly 200K and a newly installed rebuild; the latter's transaxle case would be near spotless.

I'm here to help him out because I have a spot to work on cars, and an array of diagnostic equipment that most backyard mechanics don't have. And he always repays my favors helping me with things I'm not skilled with. I don't claim to know everything, but I find these projects fun because I learn more and it's a challenge. At the end of the day if it's a complete basket case, he was warned .

 

[TheLawnRanger]

Cut part of the floor out and make yourself a first rate Flintmobile.

 

[Trav]

As Clinebarger said do a complete scan. Some things do not add up, the original engine failed so they replace it with a sketchy one from Jasper, it doesnt run properly so they put in a sketchy Jasper transmission, that whole thing is a cluster ****, is the original issue eg bad ECM still present with this engine or is this a whole new set of problems.
This is an Opel Insignia with the Opel A20NFT engine which are notorious for ECM failure and cam phaser issues among other things.

​

 

[mk378]

On old Hondas, "starts and runs, but drives dog-slow and won't EVER rev over 3000" was the classic symptom of having the timing belt on wrong so the cam timing was late.

Also consider clogged cat converter.

 

[92saturnsl2]

As Clinebarger said do a complete scan. Some things do not add up, the original engine failed so they replace it with a sketchy one from Jasper, it doesnt run properly so they put in a sketchy Jasper transmission, that whole thing is a cluster ****, is the original issue eg bad ECM still present with this engine or is this a whole new set of problems.
This is an Opel Insignia with the Opel A20NFT engine which are notorious for ECM failure and cam phaser issues among other things.

​

Got the car trailered to me today. When he bought it to tow it home his wife lost the key, left it on the trailer and they drove off. He had to get the key code from a GM dealer for $10 and had a locksmith cut an aftermarket transponder key for $30. I was able to program the immobilizer for the key when he got it here and it's up and running.

You're right- lots of things aren't adding up. For one, it's a 2011 Regal CXL with the 2.4L LAF Ecotec, not the 2.0T. I see zero evidence that the motor or transmission has been replaced-- if one or the other has, it was a long time ago. Too much aluminum corrosion on the engine block and transmission case for this to be even a remotely recent swap.

After clearing codes, the power limiter wasn't there, but the engine had a stumble at low RPM when you first take off. It quickly set these codes upon which it gave the "power limited" message:

P0089-00 - Fuel pressure regulator performance
P0172-00 - Fuel trim system rich
P228D-00 - Fuel pressure regulator 1 control performance, high pressure

Upon setting the codes and power limiting message, the car won't rev past 3K, but drives fine otherwise. I was able to get it up to 55mph pretty effortlessly, just made a quick jog near my house.

I didn't have a lot of time to spend on it, but the only thing I saw unusual in the live data was a large negative value (-25 or so) for long term fuel trim. The scan tool reads high pressure fuel rail pressure, but I don't know enough about that to make an educated guess as to what it's telling me. From what I recall it was around 2200-2500 psi near idle and low load, and would substantially drop with increase RPM (down to 600-1000psi), just revving it in neutral. It seems like a fine running car otherwise. Oil looks clean, no red flags when it came to checking fluids.

Any thoughts as to what would cause these codes? About to do some internet digging, but figured I'd post here first. Thanks in advance for any help.