2seater

There have been a few questions unanswered so far. What is the actual fuel pressure, if it runs better with MAF disconnected, do you have the old one to swap back, or even a junkyard one to try? Timing chain? How many miles? In answer to the fuel pressure regulator, it responds to vacuum level in the intake manifold, the purpose being to maintain a constant pressure drop across the injector. High vacuum, such as at idle, will reduce fuel pressure, and conversely it will rise as throttle opening is increased. It is very responsive and the relationship is approx. two inches hg vacuum for each psi of fuel pressure, so mid thirties fuel pressure at idle is normal, remove the vacuum line to the regulator and pressure should be near three bar or forty three point five psi. Heavy throttle beyond a certain tps voltage will cause the engine to run open loop, so the ecm will ignore some sensors and use the base fuel and timing map burned into the Prom.

Agree, I use Milton brand as well.

Is the rest of the story on page 2? 😣

I had a somewhat lengthy reply from yesterday that disappeared?? In any case, I wondered the same thing about the fuel pressure and made the assumption that a competent shop that replaced a bunch of items would at least do something so rudimentary, but now I wonder. I share Pagett's concern about the modern lack of diagnosing a system from decades ago. Much can be gleaned from the onboard diagnostics, but some things are outside of its ability, although some things can be inferred from other information. I believe in previous posts in this thread that the timing chain was suspect and was that ever looked into? I noted the comment about a "hole in the exhaust", assuming that means a noisy leak? If there is a leak near the O2 sensor, such as the rear manifold flange to head or the donut seal to the tailpipe, it can suck air in and it will fool the O2 sensor.

Odds are there is either a leak causing the MAF to misreport actual flow or it is defective. Best to swap sensors if you have a spare. What is the reading at idle? We just swapped MAF's on my sons Reatta for a poor or non existent idle coupled with a new O2 sensor which cured his idle. In his case, he was getting an occasional MAF code.

I call that "listening to the song of the machine". True story from my trip home after winter storage yesterday: I turned the radio on to adjust the time and such, aftermarket 25 year old Pioneer din and a half, and discovered it is non functional, then remembered I noticed that last year before I put it away🙉

Good to know and very interesting. The '90 and up do not have that big harness in that location so maybe a factory running change for a very obscure problem.

Double or triple check the spark plug routing, particular attention to the rear cylinders. It is very easy to get two wires swapped around. It has happened to me😣

Almost seventeen year lag for this answer??

I wish I could sort out all of the information presented. In the Reatta's case, the standard accumulator is .25liter capacity and the Hydac that was found as a replacement has a .33liter capacity, a bonus in capacity, and the gas pressure charge is compatible. I have tested a few on my test rig and I had one Wabco that was loaned to me to test and it appears the pre-charge is slightly higher, maybe 1100 psi or so, also a good thing in my view. It is also .33liter capacity. All of the larger capacity accumulators will require some modification of the strut tower brace, usually just spacer washers under the mounting on the drivers side. I tried "squashing" the bar in my press but it is very tough with insufficient result alone. Incidentally, I have not looked into previous posts as the correct one but that STC2784 part number sounds very familiar as the correct one. Reatta working pressure is 2000psi for pump restart-2650psi pump off, and the instrument panel indicator lights are in the 1400-1500 range to turn the lights on and 1700-1800psi for lights off.

There is a Wabco unit out there also. I had some of that stuff bookmarked but that computer is having a nervous breakdown. The Wabco is priced well and is larger capacity than the standard, as is the Hydac.

Yeah, there have been a couple of long ago stick installations, but isn't current member Daniel a Series II s/c and a stick??

I ordinarily wouldn't post in a thread like this but my view is similar to Barney's and Padgett's, long term owners that feel there needs to be a bit of defense for the Reatta. I have had my '90 since '93 and yes, they do have some quirks, but as a long distance cruiser they are excellent. Comparison to the MR2 just isn't possible, totally different animals. The Reatta is more like early T'birds in that they are personal luxury cars that happen to have two seats. It looks relatively small but it is actually one inch wider than an Allante and it weighs more than a similar year LeSabre, so sporty driving it is not. Rust can be an issue depending where it is from, not so much with the body, but front and rear cradle/suspension, but in defense, similar year Toyota pickups and similar bodies would have disappeared by now, while the chassis soldiered on. Have never caught on as a collector vehicle so if money return is an expectation, absolutely look elsewhere, but as a buyer that can work in your favor. Brakes have gotten a bad rap but work very well unless they have been neglected and the ABS sensor leads for the wheels are getting harder to find, if the Teves II type, where '91 has a more conventional Bosch vacuum booster type.

Hmm, it works on two levels. I just saw the top level too, flames on his transportation, but the Firestone idea is clever for sure.

The coolant passages are on the bottom and flow through individual small pipes, not through the actual throttle body mounting flange. Those pipes are a PITA in my opinion and I always remove them and plug the holes in the manifold for my summer only use, so I do not know how much success is had reinstalling them without leaks. I would remove the MAF body and the throttle is pretty well exposed so a reasonable job can be done without actual removal. If you do remove the tubes, the one closest to the drivers side gets removed first. It is attached to the intake manifold with a gasket and flange retained by nuts on two studs. The other end is inserted into a passage on the bottom of the throttle body which is a friction/press fit. There is a second tube connected to the opposite end of the throttle body passage and the TB should just pull off the friction/press fit tube. Tubes are black approx. 3/8" diameter.

There are splices under both seats with similar issues. If seemingly unrelated things don't work, especially on the drivers side, take a look under the other seat. I had drivers door courtesy lights, door locks operated by the trans shifter and the trunk lock at the rear, sure looked unrelated to each other but thanks to this forum, I found the problem. Oh yeah, I think the inner rear turn signal/brake high filament light bulb didn't work on each side either. The 90-91 rear flasher system is different in that the outer two turn signal bulbs are operated from the dash area as usual, but the third bulb, the inner one, is operated via a relay inside the trunk on the passengers side front. If no power gets to the trunk mounted relay, the third bulb on each side won't flash.

The module is located below the relay center at the drivers side front of the engine compartment. Best to remove the bolts that anchor the relay center and move it aside, there is plenty of slack. The wire to be cut sounds just like the one I rerouted in a different manner and if so, it is located in the big bundle harness that runs along the drivers fender in the area in question. The yellow wire comes from the passenger compartment through that large harness, and the caution to ground the module side only after it is severed is very valid.

No. Take a look at the very recent repost of the thread by DS_Porter which has a brilliant and simple solution to the LED light retract problem. The harness turns out to be a universal solution for LED lights and removing the load from the headlight switch which isn't needed with the LED.

Timeless good looks for sure,

Probably not a lot of input as this problem has come up for many years, and led lights being a generally expensive change, found the harness to be assumed in the total cost. I am no electrical expert, and went through my own headlight issues burning up expensive headlight switches using 100 watt headlights. At that point extensive factory wiring was changed to make it work, plus relays for load, and about the same time, the harness in question was discovered. To my knowledge as a non expert, the headlight door module must see a ground, such as through the low beam filament to allow the doors to close. A switched ground through a similar resistance value needs to be added to the low beam wiring or it appears just adding the switching side of a relay, terminals 85-86, has enough ground potential to act as a drain and allow the lights to close, usually with some delay.

I suspect a 5.3 LS from one of the Generals fwd "performance" cars of the early 2000's might work.

ECM runs the injectors but must have adequate fuel pressure first. Hearing the fuel pump run should be a good sign but, if it isn't producing adequate pressure, it won't run. Need to get a pressure reading if fuel delivery is suspect. One note on spark is; the ECM controls spark timing once running but the initial startup is done through the crank sensor and ICM under the coils. Injector operating system is simple although the control is not: injectors are supplied a constant 12v when the ignition is in run, the brown wire to each injector if memory serves and the ECM provides the timed grounding on the other wire to complete the circuit and open the injector.

Interesting. I guess it would make sense the Bonnie would have such a thing if anything did. I wonder if the LeSabre T-Type from 89 may have as well? I have seen on the Fiero forums those people do a lot of engine and transaxle switching, focused on performance for the most part. Our friend Ryan from GM Tuners may have some ideas.

What vehicle came with a 4T60 in the 3.33 ratio? Not saying it doesn't exist, just that I have not ever heard of one. I know the ratio can be changed by swapping sprockets around for the chain drive and that multiple possibilities exist.

2.97 One note on final drive ratio is the 91 used a slightly taller tire so the effective ratio is 3.25 for comparison sake to the earlier cars. The "C" engines have a quicker torque rise than the "L" so that may be part of the reason for the gear change??