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car runs rich! 7 cel codes!! help please!!

  • Thread starter Thread starter V ocho!!
  • Start date Start date Oct 14, 2009

V ocho!!

New Member
Oct 14, 2009
8
0
0
Oct 14, 2009
#1
  • Oct 14, 2009
  • #1
well, my 00 gt convert has been running very bad lately. when the car is cold the car runs fine, it has great power, but once i been driving it for a while the car starts to sputter, and then when i push on the accel pedal the car gets stuck at like 3000 rpm and wont go up, so its kinda like the car revs but no power. it gets even worse as i drive it. im at a red light and the car sputters like its about to turn off. and one time it actually did. so what i did i thought it may need a tune up so i changed the plugs, got a new air filter. then i took to a shop and they told me that Cel came on and i needed a Maf and cylinder 5 was misfiring. so i changed cylinder 5 coil since the plugs are brand new.

i took it to a muffler shop and got the cats gutted out, i put a new tps sensor thinking that was the problem, i put a new fuel filter also. the shop checked the fuel gauge and said it was in range, and also the tps sensor. i also bought a MAF. and now i got these 7 cel codes!!

  1. P0420
  2. P0430
  3. P1132
  4. P1152
  5. P0300
  6. P0301
  7. P0305
 

joshjwc9

Active Member
Jun 12, 2006
1,095
17
39
Palm Harbor, FL
Oct 14, 2009
#2
  • Oct 14, 2009
  • #2
P0420 Catalyst System Efficiency below Limit - Bank No 1.
P0430 Catalyst System Efficiency below Limit - Bank No 2.
P1132 Lack of Upstream Heated Oxygen Sensor Switch - Sensor Indicates Rich - Bank No. 1.
P1152 Lack of Upstream Heated Oxygen Sensor Switch - Sensor Indicates Rich - Bank No. 2.
P0300 Random Misfire Detected.
P0301 Misfire Detected - Cylinders 1-10.
P0305 Misfire Detected - Cylinders 1-10.

First I would check for any vaccuum leaks before the throttle body and in the pcv system. Then check for any exhaust leaks around the front most o2 sensors.

The first two are related to your removal of the catalytic material inside the cats causing the o2 sensors to read bad.
Do you have an exhaust leak? (That can cause almost everything related to your issues.
Make sure your wiring to your coil on plugs on cylinder 1 and 5 are not frayed. Then check the rubber boots for any cracks on every coil, because the spark will arc to the cylinder head (happened to me and shot a p0302 code and it was cylinder #4 that was misfiring.)

After you do these checks it may possibly be an o2 sensor going bad. Or, the gasket between the passenger side manifold and midpipe (that was removed when they did your cats) went bad (this should always be replaced when servicing the exhaust/transmission/anytime the midpipe is removed.)

Good luck!
 

wmburns

SN Certified Technician
Aug 14, 2009
5,892
514
204
Houston Texas
Oct 14, 2009
#3
  • Oct 14, 2009
  • #3
Check O2 fuse F2.8(20a)

Let’s review what the codes say.
1. P0420 HF1 Cat efficiency
2. P0430 HF1 Cat efficiency
3. P1132 H45 Upstream O2 not switching
4. P1152 H45 Upstream O2 not switching
5. P0300 HD1 Misfire
6. P0301 HD1 Misfire
7. P0305 HD1 Misfire

Codes 1 and 2 are from the catalyst gutting so we can ignore.

Codes 5, 6, and 7 are various misfire codes. Careful reading of the Pinpoint tests state to ignore if selected other codes are present (which they are in your case).

Codes 3 and 4 use pinpoint test H45 which deals with the upstream O2 sensors not switching. I believe the PCM has gone into "limp in" mode which is why it will not rev above a certain point.

I could tell you to check for vacuum leaks and such (which are good things to rule out). However, I am going to go out on a limb here. Since you recently took the car to a shop to have the cats gutted, let's start first with the O2 sensors.

Check fuse F2.8(20a) in the Central Junction Box (CJB). This fuse powers the heated O2 sensors as well as power for the signal return. If blown, the O2 sensors will not work at all. If the fuse is blown, check the pig tails of each O2 sensor for cut/burned/chaffed wires.

If you have access to a scan tool, monitor the O2 values and look for changes. If no changes at all, this adds additional credence to a problem in the O2 circuit.

If this doesn’t fix it, let us know and we will dig deeper.
 

V ocho!!

New Member
Oct 14, 2009
8
0
0
Oct 14, 2009
#4
  • Oct 14, 2009
  • #4
ooooo ok, well i changed the coil for cylinder 5 which is why i was wondering y the misfire still happens, but as far as cylinder 1, which one is that? i been told several times but i keep forgetting. also i am gonna go back to the muffler shop to see if maybe he can spot any leaks. the weird thing is though, even before he touched my exhaust this problem was happening. as for the 02 sensors, how will i know if they are bad, and which exact one? the ones closest to the headers or the ones going towards the mufflers? and which hoses should i check for leaks? i am not very car savvy, thats y i wanna learn. thanks guys for your insight i was jus about to go crazy!! this car only has 79K miles!!!
 

wmburns

SN Certified Technician
Aug 14, 2009
5,892
514
204
Houston Texas
Oct 14, 2009
#5
  • Oct 14, 2009
  • #5
Cyl#1 on car's Front right.

Cyl #1 is on the front right. Cyl #5 is on the Front left of the car.

The upstream O2 sensors are the ones closest to the engine. Bank 1 is on the right.

Do you hear any exhaust leaks?

The codes indicate that NONE of your O2 sensors work. What are the chances of all (4) going bad at the same time? It could happen but its a long shot.

Change them if you really think it will fix your problem. But I wouldn't until the fuse supplying power has been verifed.

There usually isn't a short cut. Sometimes you have to take the steps.
 

wmburns

SN Certified Technician
Aug 14, 2009
5,892
514
204
Houston Texas
Oct 15, 2009
#6
  • Oct 15, 2009
  • #6
Status?

Have you found the source of the problem?
 

fast97gt

Active Member
Jan 2, 2007
1,082
2
49
north carolina
Oct 16, 2009
#7
  • Oct 16, 2009
  • #7
po300 random cyl. misfire
po301 cyl.1 misfire
po305 cyl.5 misfire
and to fix the cat efficiancy codes 1 of 2 things gotta happen, put on new cats, or mil elims.
now with the car running rich it couldve washed the plugs, try replacing them. but fix the catalyst problem first.
 
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