gopher_6_9

Little info about myself. I have been into cars since I was 10 years old, built several minitrucks, several offroad machines, 4 wheelers, former mechanic for ford for 5 years, etc. However this is my first rotary so I have have a few questions....


I got a 1990 turbo model 5 speed, milage is unknown at this time (previous owner swapped clusters because of an electrical problem).

1. At idle it acts just like a massive vacuum leak, IE I have to keep my foot on the gas to keep it running. Are there any common problem areas to look for a vacuum leak on these cars? I won't have an assistant till this weekend and can't run it long (see next question)

2. Guy I got it from said the radiater leaks...... put water in it last night and it appears that the only leak I saw was coming from the drivers side back of the engine bay, roughly around the bellhousing area, maybe top of the motor, maybe a hose I couldn't see, any ideas there? again not a problem to find, but if there is a common problem area it will keep from from unneccesary removal of parts trying to locate it.

3. The sunroof is inop, I have not gotten into tearing it down yet, but I did find what appears to be parts of the sunroof motor laying in the storage bins and the panel seems like it may be loose (you close the door and it moves some) is it possible to completely remove the motor and the roof not leak? that is what I am thinking the previous owner did.....


Appreciate any help or advice, I am searching old posts and downloading the service manuel right now.

sktrowley

first thing i would do is a compression test

Aaron Cake

iTrader: (1)

Any of the vacuum hoses. On the TII, a common spot is the TID (turbo inlet duct). They crack.

There is a heater hose on that side which is a common failure. Check the Factory Service Manual (see FAQ) for the exact location. It's basically under the oil filter so it gets soaked in oil and softens up.
Sticky and leaking sunroofs are common problems caused by junk on the tracks and in the cables. A search for "sunroof fix" should turn up all the info you need to fix it.

gopher_6_9

While I have not done an actual compression test you pull the plugs (yeah not scientific by any means) and it has good compression, starts up within 1-2 rotations of the motor (as long as you give it about 1/16 throttle or so which also leads me to believe vacuum leak) and even if you shut it off shortly after starting it it doesn't flood.

I will run a compression test when I can get around to it if for nothing else to settle my own curiosity, but like I said I have enough experience with cars that I am pretty sure that compression is at least in the good range and my priority right now is finding the vacuum leak and fixing the EXTERNAL coolant leak...

Oh and I really appreciate the responce, i am not just blowing you off.

gopher_6_9

Aaron think you also, I must have missed that heater hose last night, but the lights in the shop are dim thanks to a $250 ballast going out in the only open bay I had, but I have the manuel now and will work on it more. Yeah I found mucho info on the sunroofs now.

Evil Aviator

The heater hose usually has a pinhole leak that is nearly impossible to find unless you heat up the engine first. While any spilled oil can deteriorate the hose, the most common cause is from oil leaking from the oil filter pedestal due to broken o-rings. When my car had this problem, the new hose failed within a month.

toastiepenguin

iTrader: (3)

i use carb cleaner to troubleshoot vacuum leaks on my motor, just becareful where you spay it. when the carb cleaner hits a leak the idle will change due to obvious reasons. works like a charm...o ya it is easier to do this when the engine is nice and warmed up because the carb cleaner evaporates right off anything it hits.

I'm sure you have used this method before though.

-Jon

gopher_6_9

OK, did some work last night, still didn't pull compression (my gauge wasn't at the shop, not sure where it is), but I did do a little diagnosing.

1. The "radiator" leak the guy thought it had appears to be the cap, the only time it does it is if you rev it up to say 4grand with the t-stat open then it leaks around the cap.... There is no rubber left on the cap, but then again for an original radiater cap with 100+k on it what do you expect?

2. The idle problem. There does appear to be a leak in the hose that attached the airbox to the turbo down where it connects to the turbo and there is duct tape on the hose as well so.... where is the best place to get a replacement for that hose?

3. ECU code 12. TPS sensor full range. Didn't have the damn wiring schematics or pin outs there last night so I couldn't adjust (was't sure which wires to hit) but I am assuming it is simply out of range. You unplug it and it revs high but no more jumpy idle, same thing if you hold the gas just a little.

Aaron Cake

iTrader: (1)

There aren't a lot of choices. You can get a new one at the Mazda dealer for a good sum of money, you can get a used one that is probably ready to crack, or you can make your own with ABS plumbing bits (or metal tubing if you are good at that stuff).

Clean the TPS contacts in the harness, then go through the adjustment procedure.

gopher_6_9

Thank you aaron.

Yeah I have been looking at just fabbing a plastic/metal pipe and using silicon connectors, just didn't know if somebody maybe made something like that at a decent price or not, oh well, time to fab.

Yeah I cleaned the old dielectric grease from the connector last night but the adjustment is still off, got my pinouts and stuff tonight so it should be running by this afternoon.

gopher_6_9

Alright got to take it out Sun. thanks guys.

1. car has good compression 115-120 range.

2. one side of the TPS is fried (14 ohms at WOT), so I have one on order

3. The plugs where so fouled it wasn't funny, starts and runs much better now, even though I have 2 plug wires that are questionable... (will be replaced tonight).

So thanks again, much better than what it was and when I finally get the sensors and everything in and the cats removed this thing is going to haul ***. took it out yesterday with no tps on it and if I would roll into the throttle, damn you talking about getting plumb *** sideways.