Question about 2003 Nissan Altima

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I've gutted all my catalytic converters and car still wont accelerate smoothly or go over 80 mph

The dealership told me it was a clogged Bank one cat and I had it gutted, my car doesn't allow me to go over 80 mph unless its cold/winter but everytime it warms up, my engine light comes on and car wont accelerate pass 80 mph, it gets up to 80 mph and the the injectors shut off and the speed needle has to go back to 60 mph before i can resume driving/accelerating, it does this faithfully, so now im goint to change my speed sensor and clean my mass air flow sensor, I've already gutted and cut off all my catalytic converters

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Gutting the cat converters was not a smart thing to do
the ECM needs feed back from the sensors to regulate the air/fuel mixture and now you expect it to do the job with half the sensors removed
like trying to brush your teeth with no hands
replace the cat converters with new ones then run the fault codes to really find the problem area

Posted on May 05, 2017


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Posted on Jan 02, 2017

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SOURCE: Hi..Im driving a Nissan Presea

I too be live first thing to check oxygen sensor, possibly fuel filter . Hope this helps some.

Posted on Jun 10, 2011

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07 suzuki xl7 po420 code. Oxygen sensor bank 2 sensor 1 i believe. Location in the engine. Thanks..

the cold from hell,,
CAT monitor. know it well, too well.

no its not that.
the code tells that engine has a lazy or dead cat.
no engine stated.
its and XL-7 not and XL7, they are different cars.
3.6L V6
bank one is failing the person who told you bank 2 is full of beans.

"Catalyst Efficiency Below Normal (Bank 1)" SM quote. we change the front B1S1 front sensor first.
then the B1S2, sensor next.
then the CAT if sure no exhaust leaks are on Bank1.
S1 is front
S2 is rear
bank 1, is cylinder 1 side
bank 1 is,, right bank, usa is passenger side

look for leaks first in exhuast
then bad 02s, on right side , damage to wires.
the new sensors.
then new cat, $$$$$$$$$$$$$$$$$$$ last

Mar 12, 2017 | 2007 Suzuki XL-7

1 Answer

Have a carnival and it is missing and no guts when cold but does go ok when it gets to operating temp but still is very sluggish

Unsure what a Carnival is, but generally could be bad coolant temp sensor, clogged cat converter.

Jan 13, 2015 | Cars & Trucks

1 Answer

2002 Ford Escape XLS 3.0L 4WD Firewall side Catalytic gets TOO HOT and melts insides?

Replace all of the ignition coils. You will pay about $450 in parts. That will fix your problem. It fixed mine.

Jan 20, 2013 | 2002 Ford Escape

1 Answer

2001 saturn sl1 doesn't go past 30 mph

it sounds like a plugged cat converter in the exhaust

Jul 01, 2012 | Saturn SL1 Cars & Trucks

1 Answer

It runs for 5 minutes and then dies,trying again and wont star,wait 1hour and it starts for 5 minutes snd then dies.have new pump,new fuel filter,and coil replaced and still doing the same,what could be...

Have your exhaust system checked for restriction. That may be hard to do, unless you can get someone to come to you, get it towed, or have the wherewithall to do it yourself. Often, a clogged cat converter, will let enough exhaust through to idle when cold, but as the guts of the cat expand, the flow will be cut off. Not always the case, but I've seen it happen enough times to suggest it. Another way to check this, is to remove one or both(depending on your setup,) of the upstream(pre converter) o2 sensors. If this makes a big difference, suspect the cat.Also, when idling, does it start to run rough for a few seconds before it quits? If so, push the brake pedal when it begins to run poorly. An engine with a clogged exhaust will have very poor intake manifold vacuum, therefor, the vacuum assisted power brakes would feel much different. The brake pedal would seem very hard to push, as though the engine were not running. No guarantee,but that gives you some things to check. Let me know if you have any more questions. When I can't lay hands on the car, test it, hear it, or see it, this can be a bit of a process sometimes.Hang in there!

Feb 11, 2012 | 1999 Plymouth Grand Voyager

1 Answer

O2 sensor bad, when I have auto zone hook up and test they do show o2 sensor bad, but the codes are saying sensor 3 and 4 are bad. it doesn't say "bank 1 sensor 2". how do I know what...

You will have a total of 4 O2 sensors, two on the left (driver's side-Bank 1) and two on the right (passenger side - Bank 2). Sensor 1 is before cat. convertor and sensor 2 after cat. converter. Hope this helps.

Sep 09, 2011 | 2001 Dodge Dakota

1 Answer

It started about one week ago my 96 mercury cougar XR7 won't go over 35 mph it just revs to about 3000 rpm. I replaced the pcv and had a complete tune-up, also checked the transmission. What could...

If it revs up & doesn't go,the trans is slipping
& will have to be rebuilt

Not going over 35 with no trans issues would
be a bad exhaust converter (blocked) & or
a clogged gas filter

Tune-up is sort of a outdated term and never
is a cure for much ,unless you have ignition issues

Never have to replace any PCV Valves. Remove & clean
every 3 years

Jun 07, 2011 | 1996 Mercury Cougar XR7

2 Answers

1999 Lincoln Town Car: This car runs and sounds like a diesel at speed after it warms up and the gas mileage has significantly declined. Tune up didn't help and now I am being told that the catalytic...

There should be no difference in using an OEM or aftermarket cat to the O2 sensors-as long as it fits with no leaks, it will do exactly what an OEM cat would do, with a significant savings. When the pipes are dropped behind the cats, inspect for 'clogging'-although it does happen, your cats behind your 4.6 are not as prone to breaking up as the earlier generations of catalytic converters, so look yourself for proof that they are damaged. If you do replace the cats, the rear sensors only monitor the cats thenselves they do NOT affect the way the engine runs at all. You are being sold a bill of goods in my opinion.

May 24, 2011 | 1999 Lincoln Town Car

1 Answer

O2 Sensor Bank 1 Sensor 2

That is the O2 sensor right behind the cat. converter. When the cat is clogged it can shoot contaminates in the O2 sensor so sometime just cleaning the sensor will make it work again, if not it will need to be replaced. Mark - ABKS

Oct 02, 2008 | 2001 Dodge Neon

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