1993 Riviera and a 1996 Riviera SC

Hi ,
I am new to the list, however not new to these beautiful coupes. We have had several Reatta 1988-1991 some convertibles and others just coupes, over the years both my wife and I have been driving as our daily drivers both have a Riviera, hers is a 1993 Pearl White with White leather interior 232,000 Kilometers still running good, we have a 1991 as spares car. I drive the 1996 Riv, she is Pearl White, loaded and she has done 255,000 Kilometers, she has been running very rough as of a year now, some days she is fine to drive others depending on how she would start, i.e. starting her from cold, she will fire up with lots of zest, other times it will take a few cranks to start the engine, I need to troubleshoot her. It was minus 15 few days ago, I was driving on the highway and she started driving rather erratic as if she was going to stall on me at 110Km/h speed. The Security and the Traction light both came on and stayed on whist it started driving this way, there were no other lights on. Upon the completion of my journey at the work place in the parking lot, I decided to park her and hook her up to the OBD2 scanner by Autel, when a scan was performed it showed a DTC : 1/1 P0131 P , afterwards referred to the service manual and found that it relates to a bank 1 of the O2 sensor, though it may not necessarily be an O2 sensor problem.
It beats me, so far I have done the following, changed all the coil packs, replaced the new Ignition module located under the coil packs, removed and cleaned all the injectors and the fuel rail. I have even rebuilt the SC with new bearings as there was some noise from this area a year ago.
Should I replace the O2 sensor if so what type is better, i.e. some makes may be better than others. Anything else I should check?

cheers
many thanks for your help

Welcome!!

Welcome! It sounds like you might be dealing with a bad crank or cam position sensor problem, but hard to diagnose from here! For certain start by making sure the plugs and wires are good.

Hi and thanks for the pointers.
I had replaced with the Bosch platinum plugs they were good , except I had sent the Riv to the repair shop to have her diagnosed because of this problem, however the garage removed these plugs and replaced them with the Iridium ones , they say that these cars run better with these as recomended by the GM.
Well they even pointed in the direction of a fuel pump, as when they checked the pressure it was low compared to the specs. it too was replaced, however I had purchased the after market pump on the ebay from the U.S.A and very shortly it started making noise, so it was removed and replaced with the OE GM pump, it works though the problem is the same, i.e. lack of power.
Oh before I go any further , couple of years ago, I was driving her on the ramp, she almost dies on me as it had absolutely no power, Service Engine Soon light had come on that time and the OBD2 scanner revealed DTC P1361 code set It was traced to a broken(previously repaired: twisted together wires showed oxidation, rather than soldering it) wire harness from the PCM to the Ignition module, after this was properly soldered and heat shrink tubing fitted over it for good insulation, that problem was fixed and she ran okay.
I noticed something in the engine compartment, there are 2 x Belt tensioner , one for the SC and the other driving the peripherals , i.e water pump,Power steering pump, Air conditioner compressor and the alternator, this latter one jumps erratically sometimes. New belts were replaced just under a year ago, then again they were replaced very shortly thereafter as some pulley decided to get stuck causing the belts to rupture and break. The question is do I suspect the tensioner to be defective, perhaps because of this the battery may not be charging fully, just a thought.

My guesses:

1) Replace the jumpy tensioner and while you are at it replace the other pulleys - at least the ones that are binding.

2) If I was you I'd replace that crank sensor. they cause grief and don't set codes usually. Only way to test is remove it, hook to a meter and see if it goes open circuit if you put the plastic part in boiling water. For all that hassle -- just replace the !:$$: thing.

3) Problem I've had with Bosch plats is as they age and wear the center wire burns back into the insulator. Riv has a hi-energy ignition standard, which I imagine would do that.
What are you going to do next?

Albertj

Hi Albertj,

thanks for the information, I have already purchased the Crank Sensor, how easy or difficult is it to replace it?
Would I need to place the Riv on the hoist?
I will need to go and purchase the tensioner, just a question, I have a new tensioner from a 1991 Reatta will this fit the 1996 Riv?
Also where may I get or order the pulleys, I 'd rather change them as I do not want to have to replace another set of belts prematurely.
I plan on replacing all of the above in the next day or two.

cheers
many thanks again

I do not think the tensioner will work from the 91. The '96 has the series II 3800 which is similar, but really has all different parts.

Hi,
Thanks I will go and purchase the correct part on Monday.
I like your Black Riviera, is the hood cut and modified to show the engine bay or is a picture of the engine compartment embossed on the hood. It looks neat though.

cheers

Hi,

It's a bit of photoshop fun! We took pics of the car with the hood open and the hood closed, then erased the hood from the hood closed picture...

Good luck!

Welcome! I hope you get the problem with your 96 fixed soon!

Thanks for the info.
I have just one more question, when does the timing chain, the tensioner and the pulley on these series II need to be inspected or changed?
I did our Reatta and the 1993 Riviera around 200K Kilometers.

Timing chains in general don't have a known fail mileage. They tend to last a very long time. Idler (and tensioner) pulleys seem to fail around 100K miles +- some. (200K Kilometers sounds reasonable?)

Thanks ,
yes, it sounds reasonable ,
in that case I will do it in when the weather gets warmer.

cheers