'92 Custom Cruiser Work

So I took my 63K-mile Cruiser down to my buddies shop last week to see if he could figure out why the car was getting 14mpg and the check engine light was coming on.

He has not figured that out yet.

BUT

In the mean time, we've discovered:

- Radiator was seeping down low....took out to have re-cored, and was told it's too rotten to fix. New Radiator on order from Rock Auto.

- Rear air shocks were factory, and are blown...and I mean BLOWN. Left rear was solid oil and had no resistance at all. Guess hauling myself, my wife, 5-kids and a 110lb dog down a bumpy dirt park road two weeks ago was a bad idea... New KYB gas-a-just shocks and variable-rate springs are on order from Rock Auto.

- Transmission fluid and filter changed

- New A/C Delco plugs installed, along with new wires, cap, and rotor

- Rear axle grease changed. Limited slip additive added.

- Front wheel bearings re-packed and front-end lubed

Once the radiator comes in we'll fire the car up again and see if we can sort out the Check Engine light and then hope my mileage jumps up.

I'm also going to order new KYB gas-a-just shocks for the front to match the rears this Friday. The front shocks are not leaking, but as far as I can see are also original to the car, and are very VERY soft. When I did the same mods to my Roadmaster it felt like a new car....I'm hoping the Cruiser feels that way as well once the shocks are all new.

Pretty amazing....just wanted the Check Engine light fixed...now I've gotten carried away. Imagine that.

-Mike

Yeah, but it will feel good to have all that finished!

Plus it saves one of us from having to do the work whenever you sell it! (just teasing Mike).

Chris

brokecello wrote:

Yeah, but it will feel good to have all that finished!

Plus it saves one of us from having to do the work whenever you sell it! (just teasing Mike).

Chris

Oh you know me, I'll get it all just the way I want it and then something else will come along that I HAVE to have.

81X11 wrote:

Oh you know me, I'll get it all just the way I want it and then something else will come along that I HAVE to have.

That's the first step Mike, realizing your sickness.

Tom

My 92 Caprice needed an O2 sensor and a temp sensor before the ECM was happy again.
Hopefully, yours will be that simple, too!

[quote="81X11 Oh you know me, I'll get it all just the way I want it and then something else will come along that I HAVE to have. [/quote]

Just let me know and I'll make a trip to my in-laws out of it when I come to pick it up


I'm bettin' the plugs and wires will help ALOT. I've owned 3 91s and a 92 Caprice and they all get 17-18 mixed and early to mid 20s on the straight highway runs.

Yep. My old clunker gets right at 18 in mixed driving.

My gutless wonder wagon gets a easy 24 mpg anythime I hit the interstate for short periods of
time.Did a test run with it shortly after I bought it and manged right at 26.5 with just interstate
driving.Guess your mileage is directly effected by your right foot more than any other area of smooth driving!

I have a very heavy size 12. Get outta the way!

I get 18 mph to and from town and 24.5 on the freeway.... But I am 60 miles from a freeway. I averaged about 15 pulling my 22' Airstream, 3,200 miles. That included several mountain passes.

COL

I'd love to see mine get over 20. It got around 21 on the first tank of gas when we left North Carolina, but from then on it dropped off and since then I'm lucky to get to the upper teens.

I'll post what we find with the Check Engine light and the mileage after all this recent work.

I will say the exhaust had a strong sulpher smell. I wonder if the converter is clogged. Car has good power and does not seem plugged...but that might be an issue.

-Mike

Well the plot thickens. I went home at lunch and the springs, shocks, and new radiator were on the front porch. Rock Auto is AWESOME, that was fast.

Tossed it all in the trunk of the Electra and drove down to Troung's shop. Got there, and he was letting his apprentice Sam work on my car. Sam said "Hey Mike come look at these".

The old spark plugs were all out on a towel, and all are very gas-soaked. He also had the front of the air cleaner box off, and looking into the box still attached to the throttle body, he showed me how all around the opening for the throttle body, the plastic was wet from gas.

He said at first when he saw that he thought it was just a little oil coming from the vent tube from the valve cover that feeds into that air cleaner box, but it's fuel, so now he thinks an injector is leaking or spraying wrong, or just running REALLY rich. He was putting the new plugs in and then will put in the new radatior, and will see what it looks like when running with the box open.

Sounds like whatever this is will explain my crummy gas mileage!

ALSO, he brought me over to show me the old radiator he pulled out. He said, "See how this side is all corroded here and on the other side it's clean? Well that's battery acid damage, you can see where the acid splashed the radiator and paint on the car there too.".

Ha!

If you remember, the battery tray and area around it was rusted, and some paint damamge there. It was obvious a previous battery had ruptured before I bought the car. I re-painted the tray and other areas when I added the sedan horns, but never thought to look at the radiator near there.

Never a dull moment.

-Mike

You can buy overhaul kits for the TBI units that include all the rubber seals and gaskets if you discover you need them. That doesn't include the injector itself.

Those units also have a fuel pressure regulator in them that can fail(rupture).

I bet the OBD code turns out to be a oxygen sensor code. Keep in mind that if there's a vacuum leak or some other reason to cause the oxygen sensor to read lean, the ECM will richen the mixture up in an attempt to get the post-combustion mixture reading as it should. It will appear that the injectors are just dumping fuel because they get dirty, but it can actually be something giving the ECM a weird reading not related to the injectors.

If your mechanic is worth his salt he will put a meter on the coolant temp sensor, the map sensor and also on the oxygen sensor return signal wire while the engine is running and in closed loop. That tells much more that just trying luck at replacing parts.

Try cleaning the ground at the thermostat housing. With the engine cold, remove the stud for the thermostat housing and clean the threads, and the threaded hole as well. I had mixture issues with my 91, and that was the culprit. It is the ground for the O2 sensor circuit, and the ECM.

I found a couple of broken ground wires when I was changing engines. They went to the ground at the rear of the passenger's side cylinder head. One of those is also an ECM ground.

Did you pull the code?

You did not state whether you have a 305 or a 350.

Well the radiator Rock Auto sent is wrong. It needs adaptors to install the engine oil cooler lines, and the lower one sticks out too far...can't thread the line it...it hits the frame.






Called Rock Auto and they wanted pics. Waiting to hear back.

To answer the other questions above, the car has the 350 in it. And in regards to the ground on the t-stat housing, I cleaned/wire-brushed the stud and connections really well when I changed the thermostat a few weeks back. They're clean.

Once the radiator is in the car and it's up and running again, we'll see if we can sort out why it's running so rich.

Oh and the new rear shocks and springs are IN! Pulled the 25-amp fuse for the level ride control out of the dashboard fuse block. Position #4....hope that does not control anything else...in the owners manual it didn't list anything else.

Bad pics, but you get the idea! Moog variable-rate springs and KYB Gas-A-Just shocks.



I liked the gas-a-justs better white, but like on my Roady, they are silver now.

Fun-Fun.

-Mike

O'Reilly had the right radiator. Will send the other one back to Rock Auto for a refund.

Car is running, but still way too rich. Will pass on the codes when I know them.

-Mike

Car is showing codes 44 - O2 sensor (lean exhaust)
and 54 - fuel pump circuit fault

So the 02 sensor I'm guessing is bad, but what does the fuel pump circuit mean? The car starts and runs....?

Hey, real quick, how many o2 sensors shold this car have? 1 or 2? My '88 Cutlass just has one. Is this the same setup?

Thanks all!

-Mike

1 O2 sensor on the TBI cars.

Thanks! Ordered!

96 LT1 cars have 4 O2s!!

Sprocket wrote:

96 LT1 cars have 4 O2s!!

I remember....thankfully non on my Roady ever failed.

81X11 wrote:

Car is showing codes 44 - O2 sensor (lean exhaust)
and 54 - fuel pump circuit fault

So the 02 sensor I'm guessing is bad, but what does the fuel pump circuit mean? The car starts and runs....?

Hey, real quick, how many o2 sensors shold this car have? 1 or 2? My '88 Cutlass just has one. Is this the same setup?

Thanks all!

-Mike

It's not a bad idea to replace oxygen sensors after a lot of years. Hopefully, this solves your issue.

However, I mentioned information about why it is important to actually understand what is going on, and I get the impression it's pretty much ignored.

So, for the benefit of anyone who is interested in doing true diagnostics on a vehicle I'll again cover some simple procedures for doing so. This applies very much so to TBI vehicles, one of which I have myself.

You can take a normal, relatively inexpensive digital multimeter and use it to find out what information various sensors are sending back to the ECM.

It's not rocket science either. The ECM sends each sensor a reference voltage, usually 5 volts. The sensor can be grounded on one side and then the third leg is the return signal wire to the ECM. That's how the ECM knows the TPS voltage, the coolant temperature, the MAP reading and the oxygen sensor voltage.

All you do is get the specs for the particular sensor you wish to test, warm the car up so it's at operating temp and then go to work probing wires.

Oxygen sensors are critical to the ECM. They measure the oxygen content of the exhaust stream and convert that into a signal that goes back to the ECM, which then adjusts the mixture accordingly. It normally switches back and forth lean to rich.


The problem is, an oxygen sensor code can set for more than one reason, as I mentioned before. People look at an oxygen sensor code and automatically assume it's the sensor that's gone bad. It CAN be, but other times something upstream has happened to either lean the mixture out or richen it.

The oxygen sensor isn't smart enough to know that, it just reacts to what comes it's way. So, somebody will replace the sensor and the car still runs like crap and throws a code. If it's a lean code, like Mike has, that's telling you something you shouldn't ignore.

It means that something has leaned the mixture out and the ECM is attempting to add fuel to get the oxygen content back where it should be. If a new 02 sensor does not cure what ails, then time to go looking for vacuum leaks or a stuck-open EGR valve.

The code 54 usually means something is going on with the fuel pump relay. GM TBI vehicles also run the fuel pump voltage through the oil pressure sending unit so that if the pump relay fails, the engine will still start. It will just have a long crank because the oil pressure has to build and close the switch before the fuel pump will run.

Hopefully Mike's car is restored back to good running condtion after the 02 change. if not, a little diagnostics should resolve any problems.

Well she's alive, and as usual, I've got a story for you all.

As noted earlier in the post, I took the car to my friend Truong's (Tron) shop to see why the car was running so rich, the Check Engine light was coming on, and my mileage was so bad...and I kinda got carried away with repairs for both maintence and need in general.

I'm busy with work and kids and flat did not feel like messing with all this. Truong has an apprentice mechanic named Sam that is attending the local Tech school here, and he basically did the labor for free as a "learning experience". I figure a good American V8 tune-up, shocks and springs, re-pack wheel bearinbgs, trans fluid and filter service, rear axle service, and radiator swap should be something any wanna-be mechanic can knock out.

So all that got done, and I picked up the car Friday night. I replaced the 02 sensor before taking the car home, easy job. The rear end was sitting really high from the new springs in the back...Dad, who gave me a ride, asked if I like my new Hot Rod Rake. Haha.

At the shop, the car started right up and ran smooth. I checked all the fluids, and headed home, about 15 miles. The first few miles are in town, stop and go. The improvement of the new rear springs and shocks was felt right away, a ton of the wallow was gone, and I can't wait to put new KYB's on the front to match the new ones on the rear. I was really tickled with how it rode.

The car ran fine...until I went to get on the highway....

I got on the onramp and accelerated. At about 60mph the car began cutting out and bucking badly. Say what??? I let up a little and the bucking stopped, but any time I pressed over half-throttle the car would cut out and back off. Dangit!

I took my exit and came to a red light. Sitting at idle in gear the tach kept falling off....would feel like the car was going to stall and then it would jump back up at the last moment. Grrrrr..

The car was almost on E, so I thought maybe it was sucking up garbage from the bottom of the tank, or maybe the gauge was reading off and the car was running on fumes. I pulled in a gas station and filled up with Plus. When I restarted the car it was still barely running.

I made it home and popped the hood. Pulled out my drop-light and looked around for a loose hose or something not connected. Nothing looked out of place. I thought maybe the firing order was wrong, it felt like that, but when I first started the car at the shop, it seemed fine.

I shut the hood and went in to bed, disgusted.

The next morning I got up early and drove back down to Truong's shop. I beat him to work. The car was still running like crap...and all I could think of was that Code 54, fuel pump issue. I was sure that the car needed a new pump now...even though it had been fine when I dropped it off. By the way, I had not seen the Check Engine light since picking up the car. It was totally off now...and the car is running like crap....irony...

When Truong got there we pulled the car inside. I told him I thought it was fuel pump time. He told me I was a dumbass (friends are allowed to call you a dumbass) and that it was a miss, for sure, no question.

Sam has Saturdays off, and Truong was cursing him under his breath in vietnamese...funny to hear. We checked all the obvious things, nothing. Truong said he thought I got a bad set of Autozone plug wires. We started pulling the wires off, and he pulled #4 and said "Goddam Sam!", and showed me the wire with the ceramic part of the plug still in it. Sam must have cracked the plug when he installed it.

SO I went and bought another Delco plug, put it in, and the 350 purred like new.

Never a dull moment! I checked the fluids one more time, and drove home. Car runs super...can't even feel/hear it at idle sitting at a light now.

Yesterday I washed the car really well, and even though it was less than 1000 miles since I last changed the oil, I pulled out the jack and went ahead and changed it for some fresh Castrol GTX high-mileage and a new filter. The car had been running so rich before the repairs that I figured the oil might be contaminated with fuel.

Ran errends in the OCC last night and drove it to work this morning. She's running like new, lots of power, exhaust no longer wilts the flowers and no Check Engine light so far! I'll looking forward to seeing how my mileage is on this tank. Will pass it on once I know it.

Oh and the springs have settled down a bit now. I took Misty, Dad, and all five kids to dinner last night, and I'm sure that helped settle the new springs! Ha! Fully loaded with people, it's astounding how much better it rides. Now sag, no wallow. Nice!

Took these pics this morning before coming in the office. Sits nice! Sure am glad to have it home again!

Take care all!

-Mike





....and yes I know I need to Ajax the white walls....will do that after work.

Needs WAXING Mike,glad its running like a new wagon!

How do you crack a plug?

Also, all that attention you're giving the car and you put in Autozone wires? Shame on you Mike.

Cadet57 wrote:

How do you crack a plug?

Also, all that attention you're giving the car and you put in Autozone wires? Shame on you Mike.

....They were the better wires.....lifetime warranty....

I really only use Autoclone because they are seemingly everywhere and open more hours than the other stores too, and this is my trip car. I can always swap stuff when needed.

That's my juicy rationalization for the day. I DID use Delco plugs.

-Mike

Flasheroo wrote:

Needs WAXING Mike!

Yes sir, I know....

81X11 wrote:

54 - fuel pump circuit fault
-Mike

I'm not exactly sure what that code means. But I would check the fuel pump relay first to see if it's working correctly. Then move on from there. Oh and you might want to get you one of them their FSM's they come in handy

scoffman wrote:

81X11 wrote:

54 - fuel pump circuit fault
-Mike

I'm not exactly sure what that code means. But I would check the fuel pump relay first to see if it's working correctly. Then move on from there. Oh and you might want to get you one of them their FSM's they come in handy

$4 for a new relay is cheap insurance against dropping the tank.

Give you $2500 for it

scoffman wrote:

81X11 wrote:

54 - fuel pump circuit fault
-Mike

I'm not exactly sure what that code means. But I would check the fuel pump relay first to see if it's working correctly. Then move on from there. Oh and you might want to get you one of them their FSM's they come in handy

I swapped the fuel pump for the a/c relay that sits next to it. They are the same relay. A/c still works and car still starts.

Since doing the O2 sensor no codes have come back. Hopefully that fixed it all for good.

-Mike

Mop n Glo works great on whitewalls....and makes them really easy to clean in the future.....

81X11 wrote:

scoffman wrote:

81X11 wrote:

54 - fuel pump circuit fault
-Mike

I'm not exactly sure what that code means. But I would check the fuel pump relay first to see if it's working correctly. Then move on from there. Oh and you might want to get you one of them their FSM's they come in handy

I swapped the fuel pump for the a/c relay that sits next to it. They are the same relay. A/c still works and car still starts.

Since doing the O2 sensor no codes have come back. Hopefully that fixed it all for good.

-Mike

And where did you get that little tidbit of information from!