Golf IV / Jetta IV :: CEL Recently Came On Throwing PO420 Code
Dec 28, 2012
I own a 2003 VW Jetta GLS 2.0L 4 Cylinder and my CEL recently came on throwing the PO420 code (Catalyst System Efficiency Below Threshold (Bank 1)). So I replaced both the upstream and downstream O2 sensors. Well just one day after replacing the sensors the CEL came back on with the same code. I was wondering weather or not I should replace the whole catalytic converter or if there was anything else I should try. The car runs fine, exactly how it did when I bought it.
View 22 Replies
Advertisement
I have a 2000 jetta 1.8t. Check engine light recently came on and the code is a PO1128. I replaced the maf sensor and that did nothing but make the car run worse. I've check for vacuum leaks and found a busted line at the egr valve, fixed the line, reset the code only to have the check engine light come back on with the same code. I am at a loss now.
View 3 Replies
I have a 03 GLI 24v VR6 thats throwing a P0113 code, which is for the intake air temperature sensor. The sensor is part of the MAF sensor, ive tried 2 brand new BOSCH MAF sensors yet the same check engine continues to reoccur. Is there anything else that oculd be triggering it to come on? Is there anyway to bypass/disable it through vagcom?
View 8 Replies
I'm working on a 2003 Jetta GLI 1.8t (MT and 140,000m if it matters). The CEL has been on for a couple of weeks because of an exhaust leak throwing a catalyst efficiency code. After I make this post I'm going to run down to the advance auto I used to work at & see if I can borrow the scanner to see if there's anything new, but as of right now I don't know. I'll update the thread if I find anything.
The car started yesterday AM perfectly fine. Started again when I left work around noon. No problems with the start, idle, acceleration.. it's all good.
3 hours later I tried to start it to go pick up my kid from school but it just cranked without firing and would not start. I took care of business with the kiddo and then started trying to pin down the problem.
1. Opened the door & listened for the fuel pump to prime.. No sound.
2. Noticed the dome light is on.
3. Checked ALL of the fuses on the side of the dash.. All are fine. Turned key to listen for secondary prime.. no sound.
4. Bought Fuel pump relay & replaced.. no change.
5. Cursed.. a lot
6. Bought fuel pump.. replaced.. no change.
7. Cursed a lot more.. and cried a little too.
8. Noticed the fuel pump was now priming with the key being turned, but still not when I open the door.. Dash indicates the known CEL, but now I notice that the EPC light is on too (this could be from all the fruitless cranking drawing down the battery charge)
9. Figured I'd throw in a new crank angle sensor cuz of the EPC.. no change.
10. Shot starting fluid down the intake.. didn't hit a lick.
I feel like I'm at a dead end.. It's acting like a bad ignition control module, but there's no such thing on a vw 1.8t.
View 5 Replies
I recently had an issue with a coolant leak. the Y shaped coolant line connection went bad located under the power steering reservoir. The car got hot and the coolant light came on i immediately turned the car off and saw coolant leaking out from this.
Now today I start my car it has a rough idle and dies once it dies it doesn't start again and the epic light comes on throwing the codes
17579 P1171 Throttle Actuation Potentiometer Sign.2 Range/Performance
17951 P1543 Throttle Actuation Potentiometer Signal too Low
16497 P0113 Intake Air Temp.Circ High Input
17987 P1579 Idle Speed Contr.Throttle Pos. Adaptation not started
17953 P1545 Throttle Pos.Contr Malfunction
17976 P1568 Idle Speed Contr.Throttle Pos. mechanical Malfunction
18012 P1604 Internal Control Module Driver Error
View 1 Replies
Throwing 2 codes -
P0172: too rich
P1176: post cat 02 reached limit
Last time it turned on it had horrible air flow, it felt as though it was choking. definitely not a misfire. occasionally after spirited driving the engine would die after I came to a complete stop then worsened to cutting off when I put the clutch in at high rpms. also have a slight loss of power. I also recently added a 3" tbe and changed coil packs.
View 4 Replies
So my car has been dropping multiple codes after I scanned her and found all five: p0303, p1128, p0172, p1300, p0301. She is just a simple five speed AEG and has no mods other than a SRI. I already replaced the MAF but that ended up causing more codes and I have checked the vacuum lines to no avail.
View 2 Replies
I am stage 1 tuned and just have simple bolt ons. About a year and a half ago i had my CEL come on and it was P2400. I was still under warranty and took it into the dealer. They ran through the whole eval system along with replace my evap pump and the CEL was still on. Well then they replaced the ECU and all was fixed. that following fall i took it to APR to get ref lashed and all was well. Until 2 weeks ago. The CEL is back on throwing the same code. I believe its the ECU again and I'm waiting to get into APR to have them fix whatever it is. They believe its evap but I'm not convinced.
View 2 Replies
So recently I took my engine apart to do a valve cover gasket and Ecs tuning 2.0 coil conversion. I noticed a good amount of oil in the plug tubes so I got out my trusty soap dispenser and started pumping out oil. Pulled plugs and cleaned them (wanted to make sure oil was all out b4 getting new) also while I had it apart I wanted to take intake off, ( just to polish it and clean out any carbon inside).. Well I never ended up doing that. I removed the injector connections and realized it was to much work for such little satisfaction. So I plugged the injectors back in.
I got my car all back together and now I'm throwing 6 cel codes!! P0102 (maf) which I'm assuming b.c I took it off for so long, p0201, p0202 ( injector 1 and 2 miss), then some misfire codes p0300 (random) p0301 (cylinder 1) and p0304 (cylinder 4). The car starts runs very rough then cel comes on and blinks. I was thinking maybe the oil getting down to the combustion chamber couldn't be the best for it but it would just burn off. Only other thing I did was take off the thottle body and cleaned it.
View 3 Replies
Last weekend I installed a usp test pipe with a hfc welded in and now I am throwing the code p0160......
What this is and maybe some ways that I can fix it?? I have a hard time believing an o2 sensor is shot since the car only has ~27k miles....
View 8 Replies
What I need to do to fix these codes
p0171 system too lean bank 1
p2637 torque management
p0420 ...
View 4 Replies
The car doesn't seem to run that rough.
Replaced coil pack and spark plug wires with parts from O'reilly auto
16684 - Random/multiple cylinder misfire detected
P0300 - 35 -10 - Intermittent
16686 - Cylinder 2
P0302 - 35 - 10 - misfire detected - intermittent
16687 - Cylinder 3
P0303 - 35 - 10 - misfire detected - intermittent
I have searched and browsed multiple websites and threads to no avail. They all seem to be dead ends.
View 1 Replies
So my girlfriends's 2001 2.0 Golf (engine code AVH, 153k miles) began throwing codes for misfire on cylinder 4 and for the o2 sensor (post-cat) recently. I went ahead and replaced the spark plugs, wireset, and the coil pack. They were way overdue. The CEL went away for like 30 miles, and then came back. Now it's reading misfire on cylinder 3 and the same thing for the o2 sensor. What else it could be? Search is coming up blank, most people replaced the coil pack and the CEL went away.
View 2 Replies
A couple months ago I was hearing a hissing noise under the hood throwing the same code replaced the Valve cover, after there was no issues. Yesterday saw I had CEL and I was throwing P0174 code and there is a similar vacuum leak sound coming from under the hood but the Breather in the valve cover is not sucking in air. The Oil cap comes off but the engine starts to bog, what it could be now?
View 2 Replies
I have a 2001 Celica GT and the CEL just came on. Went to Autozone and had the code read (PO420) - they said it could be O2 sensor or bad catalytic converter. Is there any way to narrow it down before I just start buying parts to replace? Car has 140,000+ and runs great...surprisingly one of the few that doesn't seem to burn oil! PO420 diagnosis?
View 14 Replies
I purchased a 2001 Subaru Forester about 4 years ago. Within 48 hours of buying it from a dealer, the check engine light came on showing the PO420 code. The car was running fine without any problems and it was suggested to us by 2 independent mechanics that Subaru is notorious for throwing this code, so we didn't investigate it any farther besides doing a fuel system clean/flush that was offered to us by the dealer.
Lately, the car has started sort of shuddering during acceleration so we figure it's time to look into this more, but just trying to figure out where to start. From what I understand, this model has 2 catalytic converters and 2-3 O2 sensors. I've been reading as much as I can on the topic and watching videos trying to figure out our options and whether we should try replacing the O2 sensors first or just go for replacing the whole shebang. I know we cannot afford the pricey repair of it all right now so the car will have to sit for quite some time before we can do that; however, if we can figure out how to do it ourselves, we could get it done much sooner.
My questions are:What is the likelihood that this could still be an O2 sensor issue considering the shuddering when accelerating?
What other signs do I look for besides rattling in the cats to know they might be bad?
View 9 Replies
I keep throwing a P0411 - Secondary Air Injection System error. My previous pump was seized so I replaced it, and broke a few of the chintzy air hoses in the process. Now, with new pump installed and new air hoses connected, I can go about 5 days before the code comes back on.
So to recap, I have:
Replaced the air pump
Verified the new air pump functions, yepReplaced the air hoses
Verified connection of air hoses at all junctions
Checked the Secondary Air Relay for function
I have not yet checked the solenoid - unsure how to do so.
View 2 Replies
Since 1 year i have this error code in my GX 470. I have replace all oxygen sensor but after 1 day the error code is coming back. How to resolve it ?
View 14 Replies
My 2004 Outback now has 120K, has always been maintained and repaired at the dealership (except tires and battery), and has always run great! I've had the plastick-y parts replaced over the last few years including head gaskets when one cracked and made smoke. In July I got a jump from a AAA tow truck, who said my battery tested as needing replacement.
In September my check engine light went on, and the dealer found the code PO420-catalyst system efficiency. They didn't seem to look any further into causes. The cat converter replacement was to cost $2521. They reportedly tested the battery as OK as part of their routine checkup. I declined the new cat converter till learning more. Meanwhile, my check engine light seemed to cycle on, then off, then on, then off . . . every several days.
In December I had the battery checked at Sears, who replaced it under warranty. So I guess it wasn't okay after all. After that my check engine light stayed off for somewhat longer than usual, then back on for most of January. I was just about to give in and get the repair done when it cycled off briefly a few days ago.
I've lost trust in the dealership because of their battery check which differed from others before and after theirs; and for their lack of specific diagnostics. The light is back on and I don't know what to do next.
View 7 Replies
CEL came on last night, OBD code PO420, truck is an 06 f250,5.4? Btw, truck running rough, no power on acceleration, in gear at idle, runs rough....
View 4 Replies
I don't have G12++ yet because I've never had an issue with cooling before but I just noticed that my coolant was low recently. I'm in SoCal where it's been 100+ degrees more than I can remember in recent history...or it at least feels that way.
I'm going to top mine off, take it in to my tech this weekend and have the tensioner and a few other things replaced at the same time but just wondering if it's been an issue or if I should be on the lookout for something else that could be wrong.
Think it's safe to drive after I top it off or should I call a flatbed?
View 24 Replies
