Left the 1996 Fleetwood sitting too long - won't stay running

[Scot Minesinger]

My 1995 RWD Fleetwwood gave me very little trouble and the only issues were the fuel pump died without any warning, and one of the two radiator fan motors failed at 225k miles.  Other than that routine maintenance, and the car ran perfect at 254k miles when I sold it in 2005 with original drivetrain.  The majority of the mileage was highway, and my tires always lasted 70k miles.

[TJ Hopland]

I too have heard those scan too brands are decent and I believe they all have models near or under $100.   The real question is what do you expect the tool to do?   Just reading codes?  They pretty much all do that, that was part of the government mandated OBD2 standard.   Features I would look for is the ability to read live data and freeze data.   

Live data is just that, you can go through some menus and look up say the coolant sensor and monitor its readings.  That can be very handy for troubleshooting especially as things get old.  You can have a lot of issues that are not bad enough to actually trip a dead or disconnected sensor code but may be feeding bad info to the computer.   You can just scroll through various sensors and maybe catch something that seems unusual which may lead you to the problem.

Freeze data I also believe came with OBD2.   When a code is set it will also grab a snapshot of the live data at the time.  How many things it grabs may depend on the tool and or the car in question.  They all seem to give you basics like coolant temp and vehicle speed.   That info can really help narrow down issues if you know what else was going on at the time.

Other features you can get is the ability to interface with sub modules like ABS systems.  Depending on the year make and model you may also get the ability to turn off oil change and other maintenance warnings.

The next level up get you the ability to run various tests on various systems.  Things like manually operating the valves in the evaprative emissions systems or do a bleed on the ABS would be examples.  Maybe run the fuel pump to prime the system?  Stuff like that.

The highest level on newer stuff will actually let you go in and modify parameters.  This level tends to be make and model specific.   You can often get into the body module and change things like how many times the turn signal blinks as well as things like shift points.

I have a tool that connects via USB to a PC running an app.  I paid almost $300 for it and for that it doesn't do much more than a $75 tool.   It actually does it poorly because you have to have the computer and its just flaky.  The reason I bought it was you could buy what was supposedly the factory option packages to get deep into things.   Last year I had issues with one of my trucks and bought the 96-2016 GM package for another few hundred.   It works but I would not recommend it. 

When I recently bought the non running 90 CDV I was in need of an tool for that because it definitely had computer issues.  I found a used OTC Genesis system locally for I think $300.   As far as I can tell it will do 81-2005ish American and Asian cars.  It was the kind of tool that was popular with non dealer type shops.   You do have to do your research with those types of tools because some require subscriptions or modules to work so if you see one listed much cheaper than the rest be suspicious.   I now use this tool more than the expensive one.  I only have one car newer than 05 and its German and still under warranty.

I also prefer a self contained tool rather than something that has to connect to a computer.   It can be a real hassle if you need to drive the car to catch a problem.  Maybe something that connected to a phone would be OK since I have that anyway but the big pro brands don't seem to offer that.     

[TJ Hopland]

And I forgot to add when talking specifically about the 96 LT1 engine I would think the best place to look for info would be F body (Firebird Camaro) forums.   Since that was the last year for Cadillac and it was only one model and the only OBD2 version I would not expect a lot of info that is Cadillac specific or that Cadillac did anything that special compared to other GM's.   When that was a popular Corvette engine they were still OBD1's.   I think it was Firebird that got it first and they had an oddball hybrid system that was not really OBD1 or OBD2.   

[cadillacmike68]

The OBD II code is P0300 - Random Misfire.

I think I didn't get all the wires on snugly. I brought to a shop, so they can install the last one on cylinder # 2 - too hard to get to and my arms are actually worse than yesterday. They will also check  plug tightness and properly seat all the wires.

I'll look at scan tools and will probably get one soon.

TJ - yes I want one that has live data and freeze frame, because this is mentioned in the service manuals. I'll look up that genesis.

I was thinking of one that connects to a computer - I'm a computer sw engineer, but it can get cumbersome. The newer ones can WiFi or Bluetooth to a phone, which is more convenient.

[cadillacmike68]

And I forgot to add when talking specifically about the 96 LT1 engine I would think the best place to look for info would be F body (Firebird Camaro) forums.   Since that was the last year for Cadillac and it was only one model and the only OBD2 version I would not expect a lot of info that is Cadillac specific or that Cadillac did anything that special compared to other GM's.   When that was a popular Corvette engine they were still OBD1's.   I think it was Firebird that got it first and they had an oddball hybrid system that was not really OBD1 or OBD2. 

The 1996 Fleetwood and roadie & caprice / impala were real OBD II vehicles, and the P0300 confirms it because I can feel it missing.

I cannot  find an old wire set order for this car in my records, (found one for the 68) so I'm getting a wire set as well.

[Dave Shepherd]

A basic obd11 code reader is cheap.  Good thing to have for any 96 up car, of course bcm codes are unavailable.

[cadillacmike68]

I'm thinking of getting one of those level 3 Innovas, the 3160g, if I can find a reasonable price on one.

[Glen]

I have an Innova 3160 OBD2 and ABS code reader.  I also have a blue tooth reader that connects to my cell phone with the Torque app.  I keep that one in the glove compartment of my truck in case I need it for someone else’s car.  They both work well and record and playback live data.  They are really essential for working on the newer cars, on a par with getting the factory shop manual. 
I would really like to get the GM tool the dealers use.  They can change settings, run test and more.  But they run about $5000 for a used one. 

[cadillacmike68]

Glen, the newest Innova 3160g also has a bluetooth capability. Yeah a Tech II would be nice but WAY too expensive.

[TJ Hopland]

TECH 2 is/was the official GM tool and is one of the ones you have to be careful with.  I'm no expert on them but have read about a lot of horror stories about people paying good money for them and ending up a tool that really doesn't work as expected because something is missing.  That is also one that is counterfeited.   Some of the counterfeits do have some functionality and others don't.   Sounds like many of the counterfeit ones are basically the $50 code readers in a TECH 2 looking case. 

[Dr. John T. Welch]

Be very careful with the  purchase of any scan tool. The universe of these tools is divided into two basic types: scan only (unidirectional) and bidirectional.

Unidirectional instruments are the least expensive and most popular.  They allow reading of first level set codes for most OBDI and OBD II US conforming vehicles.  They also allow limited erasure of first level set codes fom the ECM.   More expensive versions allow real time views of sensor inputs to the vehicle’s ECM depending on compatibility with the scan tool. Most have DTC definitions contained in a library for conveinent reference.  These instruments satisfy  or exceed the majority of the needs of the average DIY approach to maintenance and repair.  They are  essential  for the DIYer and allow  the use of   ECM information to assist  diagnosis and repair..

Bidirectional  scanners are sophisticated and expensive.  They allow  two way communication with the powertrain and body control modules  and use proprietary  vehicle manufacturer software.  They allow very in depth  interrogation of vehicle  electronic management systems and can be used to  remotely activate sensors and actuators to evaluate their status and function. Graphing software allows minute analysis of sensors and their circuits.  They also  report staggeringly accurate and complete historical data on the vehicle’s operation and performance.  This is absolutely essential for manufacturers’ determination of warranty liability and safety/emissions compliance.  The most commonly used of these instruments for GM vehicles is branded as the Tech 2. The genuine article is made by Vertronix and retails in excess of $5000. Foreign knockoffs abound and DO NOT have the features of the real unit but are made to look identical to it.  Buyers beware.

 

[cadillacmike68]

I'm not getting a Tech 2, don't need it, but I probably will get the full featured Innova or its Actron or Autel equivalent.

I don't need a built in library of DTC explanations, although they are nice to have, right there in the tool.  I have the 2-3 volume service manuals for that.

Had a shop change Cylinder 2 for me. Cylinders 7 and 8 were the misfire culprits. I didn't have those boots on all the way.

Its running smooth as a top now.

I'll hold onto the new wires and coil until they go bad. There is usually plenty of warning for the wires and the coil can just go in the trunk until it is needed - like the power pull-down for the trunk which is there now.

As an aside, apparently ACDELCO now makes a new opti distributor for the LT1s again. For a while, quality opti distributors were nearly impossible to find.

Now if I can only stop backing into the fence while putting it away at night...

[Maynard Krebs]

I seem to remember the 100k service on these engines was significant.  Back when I was buying them it seemed like most needed that service.  I think back when you were talking dealer parts it was over $1000 in parts.   Among the parts that needed to be done was the optispark distributor and the water pump.  Did they also want the injectors changed?  When I was looking it was a big deal because they were 10 year old cars that were only worth a couple thousand so needing a thousand in service was kinda a deal breaker.

It's precisely THIS that always kind of scared me away from buying what otherwise seemed to be a great Cad, the 90s Broughams.. especially the LT-1 engine-equipped ones... and the '96s being OBD-II (which some states still require emission tests for).   I'm sure that all that HP is a blast to have 'on tap'... but the '90 through '93 ones have less expensive maintenance (i.e., no Opti-Spark).. and Chevy engines... which are so much better than the doggy Olds 307s.

[TJ Hopland]

Most of my miles were put on a 93.   Always wanted one with an LT1.  When I finally got a 96 when it was running right which didn't seem to happen often I really didn't think the performance was much different especially considering that everything about the 96 seem to be more complicated and cost more.