Odd and Even Banks on Northstar

[BodybyFisher]

Ok dumb question I know, but which bank is ODD and which bank is EVEN. I know I can pull out my manuals but I have to tune up a 95 Eldorado this morning and need the info quickly. The Eldo is missing badly and I am going to hook up my computer to it to see which cylinders are missing by monitoring the misfire counts. The owner tells me that it has the original plugs and wires, so we will see, I will probably be replacing the plugs and wires this morning. I also need to replace the HVAC fan.

I think, but I am not sure, that the bank next to the firewall is the EVEN bank, am I correct?

Thanks

[JimD]

Firewall (RH) bank is 1, 3, 5, 7.

[rockfangd]

a good way to check is if it has the original coilpacks. they are stamped with the cylinder number on them

[BodybyFisher]

Thanks guys

[navion]

As a rule of thumb, the lead cylinder on GM engines is the #1 cylinder.

By lead cylinder, I mean that if you look at the "front" of the engine, meaning the end opposite from where the transmission/trans axel bolts on. You will notice that one cylinder head is slightly forward of the other. The forward head side contains cylinders #1, #3, #5, #7.

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[BodybyFisher]

Hey Thanks Britt, hope all is fine with you, long time no see

[rockfangd]

As a rule of thumb, the lead cylinder on GM engines is the #1 cylinder.

By lead cylinder, I mean that if you look at the "front" of the engine, meaning the end opposite from where the transmission/trans axel bolts on. You will notice that one cylinder head is slightly forward of the other. The forward head side contains cylinders #1, #3, #5, #7.

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That also works well. good to know on a torn down engine.

[Cadillac Jim]

The cylinder numbers on my 1997 ETC are cast into the heads.

[BodybyFisher]

I was suppose to tune up a 95 Eldorado this morning, its missing badly. Reportedly the plugs and ignition wires have never been changed. The weather is bad so the job is postponed. Its a beautiful car, I met the guy in a local Hess station and he liked my passion for Cadillac (little does he really know, )

Ill post my experience on this tune up and what I find. I planned to hook up my autotap PC computer and monitor misfire counts to see where the problem is. If its two cylinders missing badly and the wires trace back to the same coil that would be interesting but it might just be a bad wire. I need to replace the HVAC motor and do some suspension work also.

[BodybyFisher]

Ok, I drove the car and it was missing badly and had no power. Since the plugs, wires and air filter have not been changed I changed them.

Plugs, according to the sticker on the hood, the gap is .050, the smallest gap was .060 and many were .075

Ignition wires, many had evidence of bad arching through the insulation, and 4 out of 8 had rusted connectors on the coil end and were loose. Four of the coil connectors were badly rusted. I replaced the wires and cleaned up the coil tower connectors with emory cloth.

These issues SHOULD have been enough to have caused the misfire and poor power, but no, it was still missing and didnt have full power. The CAT is rattling also, but I suspect that is the heat shield.

My fuel pressure gauge was not working for some reason so I was unable to check fuel pressure, so I bought a new one and will check fuel pressure in the morning. The owner has been having hot starting problems, which points to the FPR but I didnt find any fuel at the vacuum port at the FPR. The idle is ranging from 600 to 850, I am hoping that its the ISC motor as it clicks when the engine is shut off.

This is a 95 with OBD1, my scanner can not read misfire codes as its designed for OBD2. I am not familiar with the 95 OBD2 can someone answer these questions.

Can I get into the computer system and monitor misfires?

Is there any way to determine rich or lean air fuel mixtures in OBD1 cars?

Can I shut down cylinders within the computer?

I am getting an intermittant MAP code in HISTORY any ideas?

Does a clicking ISC mean its shot given I have a ranging idle?

I plan to swap a known good coil into each location

I plan to check compression

I am thinking this is a fuel pressure problem, a CAT going bad, bad ground, PCM, ICM or vacuum leak(s). No mechanical noise, no smoke out the exhaust, no fuel smell out the exhaust,

[Texas Jim]

There are really only two things that will cause a misfire...

Hardware... (plugs, wires, coils and related wiring)... and incorrect mixture.

Since you have already replaced the hardware... I would now look for things that would cause an incorrect mixture, such as vacuum leaks, bad fuel pressure, maybe a bad injector.. etc etc ...

Don't forget that a partially clogged cat will cause power loss...

[BodybyFisher]

Thanks Jim for the ideas and focus.

I smelled fuel when the engine was started the first time after the tune up by the FPR but see no evidence of fuel spitting.

This is a great example of the inverted cone method of diagnosis. Lots of potential causes that I must eliminate one by one. Diagnosis on OBD1 vehicles is more difficult if you ask me. What equipment can I purchase to give misfire counts, misfire location (cylinder), air fuel ratios (rich/lean), etc is there anything inexpensive or do these parameters not exist in OBD1 to extract?

[Texas Jim]

Thanks Jim for the ideas and focus.

I smelled fuel when the engine was started the first time after the tune up by the FPR but see no evidence of fuel spitting.

This is a great example of the inverted cone method of diagnosis. Lots of potential causes that I must eliminate one by one. Diagnosis on OBD1 vehicles is more difficult if you ask me. What equipment can I purchase to give misfire counts, misfire location (cylinder), air fuel ratios (rich/lean), etc is there anything inexpensive or do these parameters not exist in OBD1 to extract?

I would try to get my nose down by the FPR to smell it and smell the vacuum hose.

If you smell fuel.. replace the FPR.

I do not know if the info you are looking for would be in an OBD 1 system.

I kinda doubt it.

Remember .. that is a 1995...and computer science was pretty primitive way back then.

Windows 95 didn't even come out till October of '95.

[BodybyFisher]

ok fuel pressure is only 25 psi with the engine running and when the key is turned on it jumps to 30 then decreases to ZERO....it does NOT hold pressure.

Thinking that I had a problem with the Harbor Freight cheapo gage, I tried it on my Monte Carlo and I had 42 psi and it held

I had a FPR from my 96 that I threw in and there was NO change in pressure.

The owner informed me that he changed the fuel filter last year

I plan to swap in a different relay into the fuel pump location, but I think the pump looks bad

My neighbor stopped over and in front of the owner said ITS NOT THE PUMP because either they work or they DON'T... and completely contradicted what I had just told the owner that they can work and put out low pressure and it will cause fits in driveability.... He really didnt help my situation at all.

I said based on my experience at caddyinfo, we have seen engines run poorly because of low fuel pressure and then can pump but pump poorly. He got angry and said, I built these cars for 50 years and either they work or they don't and stomped off.......... OKAY?!?!....... I only have 15 years with caddyinfo and less NS and I have a different experience based on lots of members with pump issues and Ill trust that experience and check the fuel lines, fuel pump relay, etc before I replace the pump... I didn't want to tell him that when I got involved with the 4.9 and Northstar I needed to learn everything over, I don't think he would understand what I was saying. I try to let my testing do the talking. The owner wants to parts replace as quickly as possible and I have had to fight him to be patient and lets do the diagnosis.

So I probably have a lean condition which explains the misfire and lack of power. The ISC motor is balky and clicking like mad, when it clicks the idle ranges up to 850, that will be next.

By the way guys, I thought there was a TINY ORING at the bottom of the FPR?, I took the FPR out and was very surprised to see NO TINY ORING, am I mistaken?

[Texas Jim]

It's too bad you can't just tell someone... "You Sir, are an idiot and don't know what the BLEEP you are talking about"...

Back in the mid90's I had the fuel pump on my 84 Fleetwood Brougham get weak...

I was having problems if I tried to get in a hurry.

Driving easy and with a light foot, it was OK... but crowd it a little and it ran like crap.

Finally replaced the fuel pump and it ran fine after that.

[BodybyFisher]

I just spoke to him to clear the air and he is adament that GM pump either put out 0 or the rated pressure in this case 38 to say 42. He is 70 so he is not too much into the internet so it would be difficult to explain to him how much I have learned about the Northstar from this site. I said that while I respect his 50 years worth of experience, MY experience is that these pumps can put out LESS that rated pressure and as a matter of fact this one was putting out 25 PSI, ever after replacing the FPR with a known good FPR. So my next stop is NOT to replace the pump but to check grounds, kinked lines and the FP relay. But I am leaning toward fuel pump. Now how hard is that?, I am thinking 3/4 plywood under the tank and let it down with my garage jack what do you think?

This is a different neighbor from the last neighbor that gave me a hard time with my Deville who said I would never get it running again... I think this means my neighbors are too close to me...or I myself look like some sort of idiot

[KHE]

Mike,

Block off the fuel return line and see if the fuel pressure comes up to the 55+ psi range. If it does, then it would seem like the pump is OK and the FPR is bad. Just a thought.

If it won't come up past 25 psi even with the return line blocked, the pump is bad.

As far as the neighbor goes.... Seems like he knows everything - just ask him... He worked in an assembly plant? If so, building new cars is much different than working on 17 year old ones...LOL. I'd ask him what he thought the issue was - put him on the spot. When he can't offer any suggestions, it will quickly become obvious that he doesn't know what he's talking about. After that, when he shows up, put him to work doing the worst job possible - cleaning greasy parts, etc. He'll soon get tired of that and leave you alone.

[Texas Jim]

I just spoke to him to clear the air and he is adament that GM pump either put out 0 or the rated pressure in this case 38 to say 42.

He is 70 so he is not too much into the internet so it would be difficult to explain to him how much I have learned about the Northstar from this site. I said that while I respect his 50 years worth of experience, MY experience is that these pumps can put out LESS that rated pressure and as a matter of fact this one was putting out 25 PSI, ever after replacing the FPR with a known good FPR. So my next stop is NOT to replace the pump but to check grounds, kinked lines and the FP relay. But I am leaning toward fuel pump. Now how hard is that?, I am thinking 3/4 plywood under the tank and let it down with my garage jack what do you think?

This is a different neighbor from the last neighbor that gave me a hard time with my Deville who said I would never get it running again... I think this means my neighbors are too close to me...or I myself look like some sort of idiot

I am with Kevin... ask HIM what he thinks is wrong...put him on the spot.

If he is ADAMANT that it either works properly of doesn't work at all... then he flat don't know what he is talking about...

Windings could go bad in the pump and cause it not to run at full speed...parts inside the pump may have worn past tolerences...it may not be getting the correct voltage...

There are several things that could cause it not to put out at full pressure.

How many times have we seen someone having drivability issues and then find out that the fuel pressure was low???

If the low fuel pressure was the problem...Replacing the pump usually fixes the problem...

Give me a call if you want to..

we can brainstorm it...

[airmike]

I say have the neighbor put dinner on the line. You will be happy eating dinner and he will be eating crow

Like Kevin said about the return line, if there is a rubber section, you can possibly squeeze it shut with a pair of vice grips. I can't remember if there is a section available.

[BodybyFisher]

Thanks guys, the owner said to me,

There are people who light up a room when they enter it, and there people where the room lights up when they leave. He told me to ignore him, he ambushed me...

[BodybyFisher]

Thanks guys, I dont think I can pinch the return line anywhere this is that plastic line isnt it?, won't I crack it? Thanks for the tips.

Kevin, we think alike, it IS very different building them verses failures in the field, the ones he saw probably were either running or NOT....

[KHE]

Thanks guys, I dont think I can pinch the return line anywhere this is that plastic line isnt it?, won't I crack it? Thanks for the tips.

Kevin, we think alike, it IS very different building them verses failures in the field, the ones he saw probably were either running or NOT....

That is a good point. I remember when I checked the pump on my old Park Avenue, there was a rubber section between the fuel rail and the line that went to the tank but the line that went to the tank was metal, not plastic so I was able to pinch it closed at the rubber section with vice grips.n the risk of cracking it.

I wonder if you could disconnect the return line and use a rubber stopper held against the fuel rail end to plug it off in order to see if the pressure comes up or not. The highest pressure would be 60 psi and you could easily hold a rubber stopper against the fuel rail rnd of the return fuel line. Just a thought. My guess is the fuel pump is shot but it would be worth it to check it out anyway.

Once you do fix it and if it turns out to be the pump, you could mount the old pump to a piece of plywood and make a plaque out of it for your neighbor. You could engrave the make, model, mileage, and fuel pressure reading of the failed pump and the date...

[BodybyFisher]

Kevin, the purpose of blocking the return is to see if the FPR is doing its job and its not by-passing correct?

I swapped in a known good FPR yesterday and there was no change

But I have a question, my memory tells me that there was a tiny oring at the bottom of the FPR, I see the screen but no oring, should there be an tiny oring?

[KHE]

Mike,

The purpose of blocking the return line is to see if the pump can develop full pressure. If you swapped in a known good FPR and there are ot any kinks or leaks in the fuel line, then the problem has to be a bad fuel pump. There should be an o-ring at the bottom of the FPR - sometimes it gets left in the lower cavity and sometimes it just gets lost. The FPR can leak if the small o-ring is not present.

The worst part of replacing the fuel pump is removing the fuel filler pipe from the tank. The strap bolts can be a pain too. When I did the job on the Park Avenue I used to own, I bought new strap bolts and new clip nuts. I wanted to have them on hand so if I needed them (and I did...) I wouldn't need to make a trip to the dealer a day later because they were closed when I did the job. The new fuel pump should come with an o-ring seal and a new retainer lock ring.

If the fuel filler pipe is all rusted, it might make sense to replace that while you have it apart. I am thinking about ordering one for my '97 STS as the current one is starting to get rusty and I am concerned that it might be discontinued by GM by the time it rusts through...

[BodybyFisher]

Thanks Kevin. He was quoted $500 to replace the pump, I think I can make a few bucks on the job, the owner is looking at a CARTER fuel pump, I would prefer he goes AC DELCO. What do you think?