2seater

I resurrected my old thread to post the results and add an observation. The giant orange splice of eleven wires was indeed bad. Not just corroded but two wires actually broken. One other splice, three light blue to three light blue was bad also. All others proved to be good, as well as all splices under the passengers seat. All operations are now restored. Many thanks for the help. The observation is the same as the '89 I was trying to resurrect. There was a lot of water under the carpet on the drivers side only, passengers side completely dry. This one actually had what I would term standing water. The padding was so saturated there was visible liquid on the top. Both cars were garage kept for nine months prior to pulling the carpet, so it appears the water infiltration does not evaporate over a considerable period of time. Neither car had evidence of leaks at the rear window, the hatches behind the seat were completely dry and no telltale tracks were visible. My guess is the poor water control due to lack of drip rails allows more water in than suspected and while the top of the carpeting does dry to the touch, what gets underneath, stays there and builds up over time. Just a guess.

It's mostly hoken, at least in the case of our Reattas. The exhaust isn't really tuned in any real sense and the camshaft has almost zero overlap. If the concern is about pressure available to ensure EGR flow, the available vacuum in the inlet manifold far outweighs the exhaust backpressure. I have measured the normal backpressure in most operating modes. I installed a pressure tap in the rear exhaust manifold next to the O2 sensor. At low speed and highway cruise, when the EGR would be operational, the exhaust backpressure is <1psi . My engine vacuum shows about 12"Hg at highway cruise of 70mph. The approximate relationship is 2"Hg vacuum equals 1psi so in this example, the intake manifold vacuum is pulling approximately six times harder than the exhaust would be pushing. As to the question of raising or lowering operating vacuum, I cannot say for sure. I have operated two different engines in this car, one ported and with higher compression and the other bone stock, also turbocharged in two different configurations and as well as normally aspirated. Vacuum readings are essentially the same in cruise conditions. Those old mile-o-meters are just a vacuum gauge and if you have ever connected a manifold vacuum gauge and watch is as you drive, they are extremely sensitive to your right foot. Generally higher vacuum with smaller throttle opening, which should indicate better mileage, but it increases actual pumping losses for the engine. EGR does two things. It cools the combustion process due to the introduction of inert material, (good for emissions), and also requires greater throttle opening to maintain power, reducing pumping losses and actually helping fuel mileage.

Did you take a look in the diagnostics to see if the replacement MAF sensor is actually working? The engine will start and run with the MAF disconnected completely but responsiveness will be poor. I have used several different part numbers from the '88-'90 vin C range and have had little issue with the calibration. I have never seen a MAF sensor that looked like the original one in the photo? Maybe an aftermarket copy?

That is the best solution if you have the ability to modify. Your own conscience on the pollution question. My experience has been a slightly more guttural idle sound and a more pronounced V6 buzz on acceleration but not objectionable to me. Have you done the rear manifold modification? That tends to deepen the tone slightly. I found my old data on flowing just the rear manifold using the front manifold crossover as the inlet. All other exhaust ports closed off. Stock flow 241.5cfm and 326.8cfm ported. From observations of several rear manifolds, there is quite a variance in the quality of that inner opening, some better than others. I use a hole saw that just fits inside the pipe so I can cut the inner part of the O2 bung off as well. Not needed as the O2 seals with a gasket on the outside.

Just for information purposes: I flow tested the stock cat. vs stock gutted vs a modern replacement vs a straight 2.25" pipe. All tested @ 28" wc or about one psi. Stock cat flowed 272cfm, gutted 323cfm, Walker universal cat. 355cfm and a straight 2.25" pipe 425cfm. I suspect there is a fair amount of turbulence inside the empty housing to account for the significant difference but still a good useful increase. The straight pipe flows the best but would certainly fail a visual test.

I agree a restriction somewhere in the exhaust, likely the cat. The exhaust pipes are all single wall, so a hidden collapse should be a non-issue.

Anything is possible. If the air flow changes properly when vacuum is applied directly to the inlet of the programmer, then I would move to the next connection in line, the tee under the hood and apply vacuum there. You can also simply check for vacuum with your finger over the connection and the engine running, first at the programmer connection and then keep moving upstream towards the engine. I am not sure if it is even possible, but is the check valve reversed? The tee connection should be on the firewall side. If the system worked normally before the A/C work, what areas were worked on? I would check there. Part of the testing for proper A/C operation would be a temperature probe in the vent outlets. Did it work then?

Did he check for vacuum at the black line coming from the engine compartment? If the programmer works with vacuum applied, it is good. The vacuum connection in the engine compartment is near the firewall, directly behind the throttle body position. The line comes from the vacuum tree on top of the manifold and runs toward the firewall where there is a plastic check valve which is also a tee connection. One line connects to the rear of the tee and goes to the programmer. The line from the side of the tee runs to the vacuum reservoir for the cruise control and also has a tee that splits the line between the vacuum reservoir and the cruise control servo. If any of these lines are deteriorated or disconnected, you won't have enough vacuum to the programmer and the cruise control may not function properly either. It takes 10"-12" Hg vacuum to operate the doors in the climate control and I usually see about double that on the black line coming into the programmer.

Hi Nic, The vacuum and electrical connections are actually on the bottom of the programmers. No need to remove the glove box, but, you must remove the panel below the glove box area in the footwell. Multi-colored vacuum tubing for the actuators and a black one on an elbow that supplies the vacuum.

One of the oddities about that particular vacuum connection is the steel line actually inserts into the plastic nipple with a rubber sleeve over the joint. If a nipple is screwed in in place, the steel line will likely need to be shortened.

I would guess this is a new issue, since you know your car inside and out. It sounds like a small vacuum leak except for the normal idle completely stopped? I haven't driven mine for a while but I think it always remained well over 1000 rpm when decelerating until stopped. I think I remember the S/C engine have a bypass of some kind to unload the S/C while cruising. Maybe this is hung open? The others sensors can be monitored to see if something stands out.

That sounds like an old post of mine? In any case, I have used Casper's a few times primarily because I have met and talked to the owner several times at the GS Nationals. He also does all sorts of electronic parts for major aftermarket suppliers. That said, there are several injector services offered online and some have videos as mentioned of the different flow patterns available in other styles of injector as well as clean and dirty. You can usually find "rebuilt" injectors if downtime is an issue or, as mentioned, there may be someone almost local to you.

Upon reflection I wish I had added LED indicator lights across the terminals just to be able to watch what is going on. Could still do so I suppose? A couple other observations while testing the circuit board on the bench. If only the programmer signal ground "K" is connected when powered, all solenoids are powered and have voltage across the terminals. When the second ground "L" is connected (as it would be when installed) the voltage at the solenoids disappears. My uneducated guess is the ground is switched to activate solenoids? The second thing is, the yellow solenoid (upper air) is switched "on" when the ignition is switched on. This would be maximum air to the defrost.

The valves could likely be located inside the box after removing the original ones, however, the case is metal and conductive so isolation from the circuit board would be needed. I simply nipped the wiring from the existing coil to the connection and soldered the new ones on. I was going to remote mount them and fab. a connecting cable but I found there was adequate room to mount them on the rear and the box itself can be installed and removed with them in place. The spaghetti looking wiring is the result of the length of the supplied wiring on the solenoids. They could be extended and make it a bit neater, but I found it looks fine once the paper cover is installed These are the valves: http://www.ebay.com/itm/2-phase-3-channel-mini-Solenoid-Valve-Discharge-Ventilation-Valve-6V-12V/231026023759?_trksid=p2045573.c100033.m2042&_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D22872%26meid%3D7429476984474026221%26pid%3D100033%26prg%3D9836%26rk%3D1%26rkt%3D4%26sd%3D231026023759 There are name brand valves also available at two-three times the cost. Too rich for an experiment.

I finally bypassed the internal solenoids with four new ones mounted to the outside of the box. It works just fine now. All functions switch around as they should. It isn't pretty but the solenoids appear much more robust than the originals.

This is an updated, and hopefully more clear, photo of the pressure test rig I made. One item changed from the original post is the fitting on the bottom is a metric bubble flare on the 3/16" steel tube. That works perfectly and takes less than five minutes to run a pressure test. The only item to be removed it the steel line connection on the pump.

I have been fiddling with doing a mod like that using Pontiac quad headlights. They will just meet the Federal minimum height requirement but the look is a bit less than desired in this app. I planned to weld in the piece of hood over the headlights with the possibility of a clear piece in the front. All the adjustments to headlight aim would be accessible with the hood raised.

I must admit I am a bit stumped right now and it's also painfully obvious that I know very little about how it is supposed to operate, or, it doesn't operate properly. I powered the circuit board as it would be in the car. Ign. and ground (K). Interestingly, all four solenoids have voltage across the coil and they all click when the board is powered up. When this happens, the yellow solenoid now passes vacuum to the actuator hose and releases when power is removed. It does not hold vacuum at the inlet when unpowered. The three solenoids that hold vacuum unpowered, still hold vacuum but do not pass the vacuum to the actuator port like the yellow one when the board is powered. I had thought about external solenoids powered from the board, but the operation is apparently much more complex than I imagined.

I don't know what to think. The red solenoid got better at holding vacuum, so my original controller only has one that does not. The venting of the actuator side is open on all of them, but doesn't close when activated. It may indeed be a seal problem, but it acts more like the pintle doesn't travel far enough. It seems a shame to discard an otherwise good unit. I don't want to destroy something that may be salvageable but perhaps a dissection of a solenoid may be necessary.

As near as I can tell, you only need ground the pin on the right as viewed from end toward electrical and vacuum connections. It appears the solenoids have power at all times the ignition is on, sort of like the injectors which are always hot with a switched ground. I still need to verify but all solenoids will click with power on the ign+ connection and tap the ground on that pin. Draw is about .6 amp. Sorta curious why recycle air without a/c? According to the diagram there is always about 20% outside air when in recycle. It also has a delay built in, listed as a porous plug. Nope, I was wrong. Apply vacuum to the solenoid inlet, click the solenoid and nothing happens. I tried it on one that holds vacuum and the red one which leaked down. Nothing comes through on either one. One maybe good thing with all the trying different things is the red solenoid now holds pretty good vacuum although not perfect. Click or no click, the vacuum on the inlet doesn't change. I must be thinking about them incorrectly but I don't know what it is at this point. They are a simple mechanism. Energize the coil and the pintle inside retracts, opening the passage. It must also close the vent passage that relieves the actuator when powered down.

I will admit I am using the diagrams from a '90 FSM for diagnosing the '89 but I am pretty certain the actual moving parts are the same. Looking at the air door diagram, the defrost-a/c outlet is simply defaulted to the defrost position and it requires vacuum to the actuator to close it off for air to the dash outlets. The actual vacuum solenoid is the same as the other three, not reversed. I agree the subtle communication nuances are beyond my ability to measure. I just know there is something there and I only question it because of the sad shape some of the rest of the car is in. It looks like the FSM assumes the communication is correct if the display changes properly. More after the weekend. It will have to sit and wait.

Thanks Dave, that is one of my alternatives and I may take you up on the takeout. Was it defective? Right now I am attempting to understand how the programmer gets it's information and what it should be doing with it. Does anyone know what tells the programmer what is desired? I know the BCM has many different modes but am curious how that information gets to the programmer? I checked the data line from the BCM to programmer, tan wire in the "T" cavity but that is teed with several others. It shows a pulsing voltage under five volts and a frequency around 1kHz but does not change with a change in requested operation in the CRT, at least not a definitive change. The frequency changes between about .8 and 1.2 kHz fairly rapidly. Now that I think about it, I had the door open and the activation of the courtesy lights causes a pulsing voltage on that line also, with the ignition off, perhaps confusing my result? Any insight?

This is an '89 I am attempting to rescue. The air delivery had the typical air out the defrost only with some flow from the floor vents. I went through the diagnostic tree in the FSM, checked the operation of the actuators and vacuum supply. The conclusion was the programmer was defective. I received a replacement used programmer, connected it and no change in operation. I looked at the replacement in some depth and noted the vacuum connections are in a completely different order. I opened the cardboard cover and noted the red solenoid is in a different location on the circuit board. I moved the internal hoses around on the outlet connector to match the colors for the actuators. Still no joy on the operation. The only thing I have not done yet is compare the electrical connections in detail. At first blush the color codes appear the same although the 12v ign. wire is a different color. I then started the detailed look at the solenoid continuity, vacuum holding of the solenoids etc... I suspect the original programmer is defective and the replacement is also defective, or, is an incorrect match. The solenoid with no voltage in the replacement is the red one, or at least it has a red stripe hose connected to it internally. It is also the solenoid that is in a different location than the original.

That is what has me somewhat confused. Two solenoids in each programmer do hold vacuum on the supply side, but one is different from the other. Both do not hold on the yellow, which is supposed to be the upper so I will check to see if it routes vacuum through to the actuator side which would make sense as the default is defrost. It is still a bit curious as the neutral position for the upper lower actuator is in the middle, or split flow. All coils in both programmers do have continuity, but the curious thing is all coils in the replacement unit are centered around 76-77 ohms, and the original center around 73.5 except the yellow which is 77.5. Another curiosity is checking voltage across the coils while switching functions in the CRT. All coils at some point show 10.0-10.1 volts except the red (lower) coil in the replacement programmer which always reads zero. I would think it certainly show voltage when in the heater position but I would guess there may be bad communication with BCM or, there is a fault in the board. Should I be able to operate the solenoid by applying voltage across the coils, or would that be hazardous to the circuitry?

Thanks for the info. It sounds like you have covered the ground before. All actuators do work, hold vacuum and will switch the operations with a hand pump as suggested. Applying vacuum to the inlet of the each of the solenoids inside the controller shows two hold vacuum and two do not (yellow and red). I have a used replacement programmer that also has two solenoids that do not hold vacuum, (yellow and blue). Neither programmer operates the air direction properly. Both programmers do control the fan speed fine and also the temperature control door. I am pretty sure they should hold vacuum unless activated, but the FSM is mute on the subject. Supplied vacuum to the programmer was over 20". Cannot pump up the programmer with a hand pump as leakage through the solenoids is too bad. They appear to leak out the filter in the rear, not through to the actuators. Solenoids all show about the same (mid 70 ohm) resistance across the top terminals but that may be invalid since they are still connected to the circuit board. The CRT display changes appropriately so it would seem the feedback circuits work correctly? Is there a source for the solenoids? I might try replacing the suspect ones rather than running through a bunch of used programmers without a reasonable hope of success.