When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Restricted Performance followed by P2601 and P0430 codes
Hi All,
Just some background - I had "Restricted Performance" dash light a while ago and due to COVID I could not diagnose it properly. I was being helped by @Thermo all along as he suggested I should start with cleaning the Throttle body and do a load test of the battery. Throttle body was cleaned and the battery was showing up as 88% good when checked at a local AutoZone. Cleared the codes and drove around still got the following error codes P0171, P0420, P0430, P2601, P0303, P0305, P0307, P0300, P0316 B1359, U2515, C1986, B1318, B2139 C1A64, U0433, C1D14, U0155, B1676, B2496, B2363, U1262, B2162, B1676, B2408
We wanted to isolate the problem by first trying to change the spark plugs and Ignition coils (particularly spark plugs and coils for Cylinders 3 & 7 as they were showing up in my OBD II scanner). While we work on changing those we thought of changing all the plugs and coils as we weren't sure when they were last changed and while driving around after changing the plugs/coils I got the P2601 and P0430, which made me believe that it is a problem with the Auxiliary/Coolant Pump. @Thermo also suggested while I work on changing the Water pump it's better to change the O2 sensors as well as P0430 might be related to it. https://www.jaguarforums.com/forum/xk-xkr-x150-33/restricted-performance-p2601-error-code-coolant-pump-control-circuit-performance-225584/
1 x Mercedes A2305400081 - Ordered these from local Mercedes dealership 2 x Mercedes A0085456326 - Ordered these from local Mercedes dealership 2 x Mercedes A0005456880 - Ordered these from local Mercedes dealership
PB Blaster -
Did you find the misfire cause(s) on Bank1? The must be found and corrected prior to going any further.
When P0420 or P0430 appear, it's because the respective catalytic converter has stopped functioning and must be replaced. In my experience, changing the oxygen sensors is not going to eliminate those DTCs.
What is the battery voltage across the terminals with the ignition in the OFF position when checked with a voltmeter?
@NBCat The only codes I see now are P2601 and P0430 and nothing else. I don't know how to get the battery voltage checked. Does Autozone or any other store check that for me? Jaguar dealership did the diagnostic and told me that they need to replace the CATS (but they weren't sure if it would solve the problem) and quoted 6k for it which prompted me to start this DIY project all by myself.
Any advice is appreciated before I start my weekend project.
Last edited by nsubbu8854; 08-14-2020 at 07:14 PM.
Get the battery checked with a voltmeter as correct voltage is critical for the vehicle to perform properly. The battery should have a minimum of 12.6 volts when checked across the terminals with the ignition OFF. If not, charge the battery at 2 to 5 amps for six hours and retest. If the voltage is still below 12.6 volts, the battery is suspect and must be replaced prior to doing any other diagnostic work.
What other work has been performed on the engine to address the misfire situations? Any misfires must be corrected prior to replacing the catalysts. If I remember correctly, New Jersey has the same emissions standards as California, so you must obtain CARB certified catalytic converters as replacements. There are several aftermarket suppliers with CARB certified catalysts that are far less than what a main dealer would charge. Check with a local exhaust specialist for availability in your location.
NBCat, from what I have heard from nsubbu8854, we have resolved the misfire on the 2 cylinders. So, we are down to the restricted performance which seems to come in only after long trips which is leading me to think that he is getting heat soaking of the supercharger and this is the cars way of saying to take it easy because the inlet temp is getting too high. that is why he is going after the recirc pump for the supercharger to clear the P2601 code.
@Thermo, thanks for the clarification on progress made. Was there any discussion about the air conditioning performance as well? Has the circuit and loom been tested for the auxiliary coolant pump?
I had attempted to locate the supercharger pump and spent almost 3 hours looking for it and finally gave up. I either have to go to my local mechanic to fix the auxiliary pump I purchased or give it another shot if I get to know exactly where to look for the pump. If either of you knows or have any other threads which point to the diagram and steps to get to the pump that will be great. Youtube video that I followed is for a 2003 XJR which has a different engine layout than what I have on my 2008 XJR. Also while I was under the car looking for O2 sensors I noticed that there are 2 Upstream and 2 Downstream sensors. (1 Upstream, Downstream on the left-hand side and 1 Upstream, Downstream on the right-hand side). Now I am in a sort of dilemma whether I should change the upstream sensors on the left hand or the right hand to tackle the P0430 (bank 2) issue. Once I was back home after the disappointment, found the following instructions for a X350 Cooling Fan Motor and Shroud and still am unclear if I followed the right procedure to get to the pump.
NBCat, there was no talk about how well the A/C was working. I made the assumption that the A/C was working as it should as there was no mention of it not. i would think with the hot weather we have been having, that would have come up. I only was saying the pump because my looks here showed that people that had the P2601 code seemed to fix it with a new pump. Now, did I spend hours reading each and every post on the subject, by no means. But, it seemed to be pretty much a consensus that the code and the pump were related and the most likely suspect.
Good News I was able to locate the pump after reading the instructions provided in the following link. https://sites.google.com/willcoxonli...gercoolantpump
Initially I thought the pump was located on the driver side which it wasn't so after reading the instructions it was clear that all I had to do was to remove the front bumper and locate the pump which sat right next to the radiator. It was the factory installed OEM pump and is much smaller in size compared to BOSCH pump. I was not able to pull the cable end which is buried underneath the engine so I had to pull out the cable and cut it and then attach it back to the replacement pump. I have cleared the code and am planning to take it for a spin sometime this afternoon and see if the code comes back. Will keep you posted on the results. And hopefully this doesn't get the P0430 code back.
Hi nsubbu8854,
I have been through this exercise too. One thing that I found out is that with the ignition on, but engine off, you should be able to hear the supercharger coolant pump running when you listen at the right hand bumper corner. I replaced the pump (the old one was stuck) but didn't hear the pump running. Much later, I found out that relay 12 in the front distribution box had failed. After bridging it with an external relay, the pump started running. No more error codes and restricted performance.
Hope this helps.
Pete
@Pete M - How/where did you get the replacement for Fuse 12? Are your referring to the following fuse box diagram in the thread below? If you can provide me with instructions on how to replace the fuse it would be helpful. https://www.jaguarforums.com/forum/x...diagram-25952/
Hi
Firstly that thread is referring to the rear fuse box.
The supercharger coolant pump is fed from Fuse 24 in the Front Power Distribution Fuse Box.
There is a very good thread in this forum by 34by151 called Front Power Distribution Fuse Box dating from 03-21-2017. I used it to construct my repair.
I found that there was power to the printed circuit board relay (which you can't easily replace) R12. However, the relay did not produce any power to Fuse 24 to energise the supercharger coolant pump. So I took power from the fuse upstream (Fuse 12) and fed it via an external relay back to the downstream side of Fuse 24.
This is just reproducing what is going on inside the box, but externally. On my car this made the supercharger coolant pump run when the ignition was switched on, which it hadn't done before. It also stopped me getting 'restricted performance' errors.
Modification to work around inoperative Relay 12 which powers the supercharger coolant pump Fuse locations
@Pete M - I checked my car yesterday and fuse in 24 position is intact and is not blown away. I'll take a picture today and post it. I will check the thread you are referring to and follow the instructions.
Last edited by nsubbu8854; 08-18-2020 at 02:12 PM.
nsubbu8854,
The important thing to check is at Fuse 24, is there 12v present when the ignition is on? This was what I was missing, because Relay 12 between Fuse 24 and Fuse 12 had failed. The fuse has a metal dot to put the multimeter probe on to check it. Other probe obviously onto an earth like a bolt.
Again, with ignition on but the engine not running, you should be able to hear the supercharger coolant pump running at the front right hand side bumper.
Keep going, we'll get to the bottom of this!
@Pete M - P2601 code doesn't seem to come back after driving it a bit but I got the P0430 code back and wasn't sure if I need to change the Upstream or the Downstream sensors. Also, I noticed that there are 2 pairs each (1 US and DS on the left-handed side and right-handed side), which side is talking about Bank 2? (screenshots below are not from my car but depict the correct orientation). @NBCat I know you have asked me to check for battery voltage but before I do it I need to know if changing the O2 sensors will resolve the code. Please suggest the best course of action before I take up this project over the weekend. Also, it would be helpful to know which engine side is Bank 2 ?(P0430 points to Bank 2)
I was following the thread below which has the following instructions. https://www.jaguarforums.com/forum/x...s-52161/page2/ -Buy anti-foulers part #42002 dorman brand at O'Rielly Auto (18mm short tapered)-Get a good 1/2" metal drill bit -Take one of the two anti-foulers and drill through so the opening will be big enough to fit the o2 sensor. Hole diameter throughout the fouler should be the 1/2" -Put car up on ramps or a lift and get under your car and locate the downstream o2 sensor (this is just about the only one that is easily accessible anyway - just double check that you are getting P4030 as this is the downstream o2 sensor cat 2, same as the one I'm describing) -Use a good wrench or vice grips and remove the o2 sensor (I bashed my fingers, so try and save yourself some pain and use a mallet or something) -Screw o2 sensor into the anti-fouler, the tip of the sensor will barely fit in the opening that you've drilled, make it tight -Before screwing the o2 sensor and anti-fouler back into the cat, it helps to reverse twist the wires so that when you put it it, they untwist and are essentially normal. You could unplug/re-do the wires if you don't want to hassle with this, but make sure the wires aren't all twisted up when you are done screwing it back in.
Last edited by nsubbu8854; 08-20-2020 at 03:27 PM.
Hi nsubbu8854,
There is a whole book of things people do to get rid of P0420 and P0430 codes. The anti-fouler trick is one of them, but replacing the downstream sensors, or even the catalysts is a possibility. Note that the picture above is of a modified exhaust system. If your supercharger coolant pump is running with the ignition on, then that problem is solved. Note also that if you opened the cooling system to change the supercharger coolant pump, then you may want to top up that part of the system, as it has its own filler plug next to the right hand intercooler. You will need a 17mm hex key (allen key) to unscrew it. Check its level with the ignition on (and the supercharger coolant pump running). Attached is a procedure for this.
Today I removed the bumper and sealed the Coolant pump with heat shrink tubes and extended the cable such that it doesn't get crushed behind the radiator. Also, changed the front and rear O2 sensors on the driver's side (Bank 2) and cleared the only code which is showing up (P0430) on the OBD scanner. Will drive around a bit and let you know the status. One strange thing I noticed - Coolant liquid was completely drained out (as I recently got a error on dash - "ENGINE COOLANT LOW") and I checked the clamps while working on the pump and did not notice any leakages. I topped it off with the fluid to check and see if there is any leakage that I'm not noticing. Can anyone of you @Thermo , @Pete M , @NBCat tell me what could be the reason ??
08-14-2020 | 06:26 PM
Restricted Performance followed by P2601 and P0430 codes
I was able to locate the pump after reading the instructions provided in the following link. https://sites.google.com/willcoxonli...gercoolantpump
sometime this afternoon and see if the code comes back. Will keep you posted on the results. And hopefully this doesn't get the P0430 code back.
