I have a 90 T2 with a Walbro 255 pump. The pump has about 400 miles on it. After doing a fuel pressure test the results we received are not exactly the specs in the FSM.
The gauge showed 44 psi inline fuel pressure and the FSM says 34.1-39.8 psi. So, is my reading close enough?
Also the gauge showed 54 psi max pressure with line capped after gauge and the FSM says 71.1 - 92.4. Pretty low, but again, is that close enough?

The car runs really bad after warming up.

I did try to find these answers by searching.

thanks guys......... ashley

 

I set mine around 45,but I can't tell what the pressure is after running as the gauge is on the regulator in the engine bay.
Have you checked the Water thermo sensor at the back of the waterpump/alternator area to make sure it is hooked up?
Also the Air Intake Temp sensor at the throttle body elbow..hooked up too?

 

Yes, we just had the uim off and everything was rechecked. But, I will take another look at it. Thanks.

 

44 is probably close enough, its going to be a little rich.

for the dead head test, if the stock pump should do 70+ and yours only does 50, its bad

 

thanks, I was wondering if the "dead head" test was OK. Sometimes "close" is good enough.
Maybe I should start pricing another pump. But, the pump that is on there is almost new.

 

I'd guess your FPR (regulator) is in the loop for your 'dead head' test since a Walbro pump should generate 100 psi. That or you have a leak (probably at the pump).

Your issue is not the pump, but the stock regulator, which can't handle the flow from a Walbro high flow. Unfortunately installing an aftermarket regulator can be expensive since it's also a good idea to upgrade the lines to AN hose & fittings. That said, stock rubber fuel hose works fine.

The other issue is the fuel pump resistor circuit in the T2, which I've found to be problematic, especially when hot.

Or just go back to a stock pump and call it good.

Welcome to modsville.

 

stock regulator isn't designed for a Walbro pump

 

my car runs/drives and idles fine with the walbro, are you sure its a real walbro and not some knockoff.

I'm going to be rewiring it soon , probably on continuous 12v


as stated check the iat/thermal sensor to see if they're hooked up, I'd check their voltage on the ecu side , harness side to make sure they're receiving the proper voltage and check the sensors resistance to know they're working.

my car had a bad iat sensor and my connector on my thermal sensor wasn't making contact with the tabs on the sensor...so neither worked until I fixed them..

Rotary > Pistons

 

The fuel pump probably had nothing to do about the poor running. Last evening we swapped in a new Walbro. I took it for a ride and about 1/2 miles from the garage I heard a loud bang come from the engine. I pulled over at the first place I could get off the road. When I pressed the clutch in the engine stalled. I tried to restart it but it would only run poorly for like 5 seconds. I called my dad and he came and we towed it home.
This morning he did a compression test on it. The front rotor tested OK but the rear rotor has no compression, no bounces, nothing, zip. So, what ever was causing the engine to run so bad after it warmed up, probably finally decided to fail.

At some point, we will have to pull the engine again.
I don't know if it would be worth it to rebuild this engine again. Maybe sell off anything worth saving and get another engine for it or just piece it out and cut our losses.
In November we will have had this 7 fro 3 years and it has never been more than 2 miles from the garage.

 

Sorry to hear this about ur 7, I wouldn't give up, take what u have learned and keep on building.

 

Sounds like you lost a seal somewhere , I'm sorry to hear all this happened.

It could of been an error in the engine build if it wasn't from something else.

Is this the first rebuild you've done?

Rotary > Pistons

 

No, this wasn't our first build. I think this is the 4th rebuild we have done and we actually have rebuilt this engine twice before this. The first time we rebuilt this engine it would not run because a previous owner made the primary port way too big so we took it back out and rebuilt it with a new center iron and while we had secondaries street ported. We have just never been able to improve the terrible running once it warmed up.

 

Are you sure the injectors connectos are all hooked up where they should be? sounds like its something electrical like a sensor .

I'd just go over everyrhing, that's what I've been doing, mine was the opposite... ran like crap when cold ran good warm, now its good for both.

Rotary > Pistons

 

I don't think it would do any good to recheck everything electrical at this point.
We are planning on taking the engine back out next week. As we disassemble it we will go over everything but I don't anticipate finding any contributing factors on the outside of the engine. You never know, but after 6 months of trouble shooting i would not expect to. Maybe there is a crack in an iron in close proximity to an intake port that only shows up only when the engine was hot. I don't know.
Acording to my sig below, this is the 5th rebuild we have done.
ashley

 

well I hope you get it all fixed.

Rotary > Pistons

 

Ash, this is terribly crushing news and you must be in a house of pain. I'm really disappointed and sad to hear of your engine loss. I feel a bit of frustration, defeat, and frankly a tinge of anger. You're probably feeling these things and more and must be at the end of your rope. The patience and determination you've shown up to now have been exceptional.

The rotary engine can be vicious to those learning it's fickle and sensitive ways, but it's good to hear you're willing and able to battle-on and continue the pursuit of the reward that comes with driving a healthy, reliable rotary. It's possible, but far from simple or easy. My advice: dig until you find the root cause of the failure. Perhaps an erratic fuel system is not the problem, but a stable fuel supply is critical for any IC engine, especially a turbocharged rotary.

Be strong, you can do it, and good luck in your quest.

 

sounds like there was still a pump issue if it was only pushing 50psi when dead headed. a good pump/wiring/voltage should be pushing 80-90+psi.

 

I was going really slow when the engine quit running, like 30 - 35 mph, 3rd gear.

I know a lot of you guys have parted out your 7s. If we decide to just part it out and cut our losses, on average, how much do you think we could recoup? I know it probably is hard to guess....... but just a ball park figure.

thanks...........ash

 

it always just depends on the condition of the parts, most cars net $1k-2k being parted out unless it has desirable pieces on it like mint black interior, good engine parts and aftermarket pieces.

some cars less, if the interior is all cracked and faded, stock suspension/wheels, inoperative switches and broken engine parts. turbo parts almost always carry a premium though, because they are increasingly more rare to find.

 

About $2-3k for an S5 TII if you do it right and live near a city where locals will buy the big stuff.

 

Thanks for the input guys. Well, I'm probably not going to be able to part it out. We have way too much money in the 7 now. I quit keeping track a long time ago but I'm sure we have over $6000 in it.