89blueovergrey

Apologies for the delays on providing an update. I have now been able to take some actions and complete some more data collection. Since first testing, I have cleaned the MAF sensor and replaced the air filter. I checked the resistance across the coils and had 11.2k+/- ohms on all three. On new test drives I implemented some of the simpler suggestions that were made. I was not able to reproduce the “chugging”; however, I was monitoring ED17 – OLDPA3. On level surfaces, and with moderate accelerations, the count did not change; however, while maintaining speed on hills the count incremented rapidly, i.e. by the hundreds. As Ronnie suggested, I did tap the brake while in 4th. As described this caused a boost in RPM and the knock count stopped incrementing for a brief period. I also monitored ED07 – O2 sensor voltage. This ranged between 0.13 and 0.92, which from the service manual seems to be normal. Next step will be to take the suggestion to replace plugs and wires. I will provide an update when complete. If this does not resolve the issue, I will undertake some of the other suggestions (which, for me, would require the help of a mechanic with proper equipment). Any additional suggestions will be appreciated.

Thanks for the quick replies. I will be away from home for a few days, but will restart my troubleshooting with these ideas as soon as I return.

I’ve recently experienced a new issue with my ’89 Reatta with 140k miles. Upon ascending a prolonged hill at steady speed the engine chugs. I say “chug” because it is more than a brief stutter, or roughness. It seems the engine is completely cutting out to the point of making the car buck. This occurs across a range of speeds – I have experienced it at 35-40mph; as well as, at 65mph while on cruise control. Backing off the speed causes a return to normal function. In the limited testing I have done, I have not experienced the issue on hard acceleration, even if that acceleration is on a hill. In ‘P’ark, I have increased RPMs and had smooth running up to 5600rpm. Above that I experienced some pulsing – vroom, vroom, vroom -- at about 0.75sec intervals. I have run diagnostics and have no ECM codes. I have recorded the ECM data values (at idle), but am not knowledgeable enough to know if any are out of range. In the last 14 months I have replaced the ignition coil unit and ICM. The spark plugs and spark plug cables are relatively new. The PCV has been replaced regularly. I have pulled the MAF sensor and it doesn’t appear fouled. I have a can of MAF cleaner but have not yet been able to clean and test. (Will do next.) I don’t want to limit the thinking, but my thought is this may be a fuel supply issue – pump, filter? Am I wrong to dismiss a single cylinder issue? Anyhow, I am interested in suggestions for potential solutions or next troubleshooting steps.

To answer Barney: After reading this thread, I discovered the existence of the URO STC2784. I asked if anyone had tried this, as I would not want to repeat a failed attempt with this, nor pay more for the Wabco item if the less expensive URO item could be used. I have collected some info on the URO brake accumulator and can provide some comparisons to the GM original and the Wabco versions. I purchased the URO item for just over $100 (Rockauto) and the Wabco for around $250 (Amazon/Autoplicity). Here are the dimensions (my measurements) for the originally installed GM product, the Wabco, and the URO. GM Wabco URO Diameter (mm) 84.4 94.0 95.5 Height (mm) 116* 118 128 * The height for the GM original includes the top nipple with the hex socket, which does not go under the cross brace. GM Wabco I ultimately installed the Wabco. When installed it touched the pipe that circles the front of the accumulator. I believe the URO, while it may have fit, would have put some pressure on the pipe. I employed the two washer solution when refitting the cross brace and it just cleared the top of the accumulator. I would suspect the extra 10mm of height on the URO would not allow the cross brace to be re-installed. I do not believe the stud on the strut housing is long enough to allow the cross brace to be mounted much higher. Some notes: · I used a metal strap oil filter wrench to remove and install the accumulators. Due to the torque required (more than anticipated) for both the removal and installation, I blocked the pump/motor assembly. The service manual calls for 30 ft-lb. Removal Installation · I don’t have pictures of the URO as it was sealed in a plastic bag and since there was the possibility of returning it, I did not remove it from the bag. · After the repair I completed a brake fluid flush. I don’t know if there is a way to fully siphon or drain the reservoir, but since I could not do it, I used about 2.5 quarts of new brake fluid during the flush. If the reservoir could be completely emptied of old fluid prior to starting the flush, it would require much, much less fluid. · Upon inspection of all brake lines, I noticed a few rust areas, especially in the area of the proportioning valve. I will start to investigate replacement – there is always the next repair!

Well, I believe it is time for me to replace the accumulator in my 89 with 140k miles. Thanks to everyone who has contributed on this topic. I am about ready to purchase the Wabco STC 2784. However, I am wondering if anyone has any experience with the Uro or Dudsn brands, which have the same STC 2784 part number. The Uro is about 1/2 the price of the Wabco. Thanks in advance for your response.

Thanks for the replies. This was a lapse of memory for me. It is reattaowner.com that I was looking for, but reatta.com stuck in my mind and a few mentions of it on this site had me going in the wrong direction. Thanks again for your help.

I have been attempting to access reatta.com, but am getting a message that the domain is not in use??? Does anyone know what has happened? If the site is gone, is the content available elsewhere? I would hate to see the information disappear. Thanks (Sorry if this has been discussed in a previous post, but a search did not return a similar discussion.)