Hey guys, believe me I've searched the threads already and can't find the info..... I am getting a code 45 on my 95 D1 and it begins to idle really rough to where it almost wants to die @ idle while stopped. Then when I go to take off it has very poor acceleration. But seems to run ok at speed (45-65 mph). No popping/missing. I thought I had read in a post about the cats maybe plugging up and causing a symptom like this, but not sure. The O2 sensors look to be a 2 wire setup with splice connectors on them. No plug-in wire harnesses. So they may have been replaced by a PO. I also have about 178K, so cats are most likely OG and need to be replaced anyways. But any help/info would be great.. Thanks in advance guys

 

Darn those PO's!!!

The correct Oxygen sensor for you truck is a 3 wire, Titania sensor part number NTK25016... NOT 2 or 4 wires and not Zirconia based. pay no more than $100 a piece for em (through AB, Will Tillery, PT Schram, BP of Utah.... )

You should start there by replacing with the correct component. Once the right o2 sensors are in place you can still get the 44 or 45 codes through rough running, usually a misfire or a very rich mixture. That is where I'd check the simple stuff first like cap, rotor, leads, plugs. Then make sure the MAF is cleaned. Do you know how to clean that correctly? it is easily damaged otherwise. also make sure the IACV (cone and plenum seat) is working properly and clean. Please keep in mind with those codes, they do NOT necessarily tell you there is a fault with an specific component. Like in this case you could still get that code even if the o2's were brand new and correctly connected. OBD is just a troubleshooting guide.

And if those are the original cats then they are doing absolutely zero... might as well replace them.

 

Is it worth going with OE cats or an aftermarket universal cat from Summit racing, etc? I am ordering the tuneup parts tomorrow. I took stepper motor off and cleaned it with carb/choke cleaner. Months ago when I bought the truck, I took the MAF assembly out and used MAF cleaner spray from Oreilly's and just sprayed it really well and cleaned where possible. Didn't disassemble it at all. I will try the tuneup first as IT definitely needs one! And go from there... Thanks

 

As for cats, I got rid of mine since I could. My opinion is that the OEM stuff works just fine and lasts a long time. So if it is cheaper and has the same chemical reaction process as required by Big-Bro-EPA then that's good...polished stainless is more of a show thing since all semi-decent cats are made from a low grade stainless anyway. With cats it is more about the mileage and state of the engine tune. Rich is bad for cats.

The hp increase you can gain from super flow cats is minimal but does exist. Sound is good-er too.

It's up to you, the local laws and cash flow. But FWIW, I like not having them on my pre OBDII rovers. Downstream sensors are a bee-atch.

 

Well, no smog laws here either..So thats a plus for me. I'll look into the correst O2's and try that. Cat's are going away.....I had a 95ford ranger 4cyl before the Disco and got rid of the cat on it and it had 2 O2's, one upstream and downstream of cat. NEVER through any codes... I wrapped pipe with heat tape around O2 locations to keep as much heat into those locations. That was a tip by a cert. ASE mechanic. Must of worked LOL...... Gonna tune it up first, then look at O2's and go from there. Thanks

 

On your 95 you (not legally of course... that's my weee disclaimer) will not incur a CEL or any other warning indicator if the cats are not there since that MY only has upstream sensors.

And another item worth losing IMO is the rear resonator... the center muffler I kept in place.

 

HAHAHA........the resonator had fallen off long before I got the Disco....apparently. Cause it wasn't there.Just added a turn down to route exhaust away from rear door...Parts on the way from Rovahfarm

 

Ok, so I got the tuneup parts. During the tuneup I was replacing the pass. side plugs and looked down at O2 sensor....The leads were just hanging there, not hooked up to sensor! They are a 3 wire connection and are spliced with connectors. So, either they had been replaced from PO or removed by a PO and spliced back in.And from twisting, the wires may have come loose. So, I cleaned it all up and rewired it. I hope this was the reason for throwing that 45 code....not being hooked up! lol......But as for the tuneup, it now runs like a champ. I will see if it throws a code here this week . If it doesn't, maybe now I know why.

 

Ok, so last weekend i tuned up the Disco. New autolite coppers, allmakes cap& rotor and 7mm plug wires. Started it up and ran like a new truck!! Adjusted the timing to 6btdc. As it was out of timing a hair....Well, while replacing plugs on pass. side, I looked down at O2 and wires are completely disconnected from sensor! This must be why I keep throwing the code 45.....Right? Well, I resplice the 3 wires. Sweet, now I should be good...WRONG. So I drive maybe 2 miles total back and forth to work each day. Cool, no CEL all week. This weekend I put some miles on the truck. At the stop light, BAM! CEl lights up and the truck starts too idle slightly rough, no where near as bad as pre-tuneup, but still noticeable. Now my question is, My O2 may be bad(@ 178K, most likely). No prob, I can replace that. But with a fresh tuneup, what else should I start checking? TPS, IACV, MAF, Injectors? Cause it runs/drives like a champ until light pops up.

 

Does anyone have any suggestions on where to begin looking at my problem? Should I check fuel pressure at the rail? Clean MAF, IACV, TPS? It runs and idles fine until it gets to running temp and it idles say at a red light, about 2 minutes.... Just need to be pointed in the right direction. Thanks guys