teddyca

iTrader: (37)

I had a set of the ebay headers, high flow cats, and a bassani xpipe installed along with my Flowmaster catback that was already on the car. The sound is simply amazing, but the car runs like crap. If I get on it at all it backfires and falls flat. If I am more then 20% into it the car will pop when it shifts any gear. Try and go 50% or more and it will stumble and backfire horribly. I also installed a set of Taylor Thundervolt 50 wires with a new set of NGK TR55 plugs. Because I had a local shop do the install I bet the gaps were not double checked. My first thought was the wires so I am considering swapping back in the new OE's I have. Just because the wires are significantly bigger I can not see why it would mess with the car though. Also I read the O2's could have possibly been swapped but not sure what affect I would have. Note the car does not smoke and has not thrown a CEL??? Please help

Also note- I just went outside and pulled one of the new plugs. I confirmed that a set of NGK TR55's were installed. The one plug I pulled was also gapped at .55 I noticed that there are TR5 plugs gapped at .35 and the TR55's at .50 I wish they were checked before installing. could this be my issue. With less then 3 miles on these new plugs, they were already pretty white so I assume the car is way lean. I do have a Fuel pressure gauge and that was fine.

Car is a 00 C5 Coupe.

racecar

What got screwed up?? Pull all of the plugs to see if the gaps are 0 on some.
Are the 02 sensors plugged in the exhaust. Start looking for wires that are not connected.

turbotko

If the precat O2's are swapped it will cause hell with the fuel trims. I'm betting it's ignition related though.

teddyca

iTrader: (37)

I know for a fact it is either ignition or the O2 swap but which. My plan was to initially swap the wires back to OE and check gap on ALL the plugs. Others seems to really think the O2's are swapped. How could that happen. I realize there are 4 but would they accidently be swapped left to right or front to back. If I remember correctly, the fronts would not reach the rear?

Fastbird93

iTrader: (10)

That's what I'm thinking.

teddyca

iTrader: (37)

I am going to check that and also verify that the pass. harness is in the drivers side O2. I also need to make sure the O2's are BEFORE the cats. I hope it is that simple. can I just unplug the harnesses and swap them or do I have to pull the O2's?

Slowhawk

iTrader: (12)

First I'd check to make sure the coil packs are pluged in. Then I would switch the wires back to stock.After that it would be the 02's.

Or the first thing is to have someone scan it.

teddyca

iTrader: (37)

I am going to actually swap the wires back and check the DIC for "C' or current codes. I'll let you guys know how it turns out.

santiago

iTrader: (28)

i ran those wires fo along time it shouldnt be the wires... check to see if all the plugs wires are connected with the plugs correctly recheck your coil packs and recheck your o2 connections.

teddyca

iTrader: (37)

Damn I checked everything and it all looks fine. I swapped back to the OE wires and it did not change. I then checked all my connections and they are all fine. Lastly I looked at the O2 sensors and there is no way they could have been crossed. Without O2 extensions they would NEVER reach. I am stuck. I also got no codes in my DIC. All were History and none current.

santiago

iTrader: (28)

chake the brake booster....the line might have been removed for more room and not put back on.

teddyca

iTrader: (37)

I looked at that and it seemsed loose but why would that affect the car? whouldn't that just be the brakes or could I have a vacumn issue from it.

santiago

iTrader: (28)

one time i started my car with it off and it turned on then shut right back off.

Sigforty

Are the O2 plugged into the front O2 ports? The rear O2 only confirm that the cats are working properly. The front O2 sensors control the fuel mixture. Normally the O2s get crossed because they are in the headers at an angle and you have to cross the wires over to get back to the side they control.

teddyca

iTrader: (37)

Nope O2's look good. I think it might be a vacumn leak of some sort. I have someone with a EFI Live system coming over later to look into my issues.

Bad30th

iTrader: (13)

Did you check the ECT sensor ? The car will run like crap if the PCM can't tell what the coolant temp is, and the sensor is right by the driver side header and commonly gets broken during header installs...

Just a thought.

Rob (Bad30th)

teddyca

iTrader: (37)

Rob- This has been mentioned several times. I did not check that particular sensor. So here is a few questions in regards to it.
Where exactly is it located?
would the car still show the temp. properly?
Whould it immediately throw a code if damaged?

Bad30th

iTrader: (13)

It screws into the front of the driver side head, right by #1 exhaust primary.

The factory temp gauge, although slow to respond should jerk around when the car stumbles. If it only does it under load and runs fine the rest of the time it's probably not this sensor, but thought it would be worth mentioning.

The EFILive will be able to scan the coolant temp and it will show if it's way off.

It may or may not throw a code right away. My friend's Camaro didn't when his ECT sensor wiring got damaged, but my HPT scanner showed it was like -30 degrees outside, heh. His factory temp gauge did jump when the car stumbled.

Rob (Bad30th)

teddyca

iTrader: (37)

Great I will look at that. To be honost I really never checked to see it jump around, but as it ran like **** I made a point to continue to look over all the gauges in the car. I hope this sensor is just unplugged. I don't want to know what some of this crap costs. Leaving work in about 45 minutes to tackle the job.

Sigforty

Just out of curiousity how many miles are on the car and have the injectors or fuel filter ever been changed?