will crank over but will not start... 1989 mazda gtu rx7
Asked by Jbrown78 Jan 23, 2013 at 10:10 PM about the 1989 Mazda RX-7
Question type: Maintenance & Repair
ok i have a 1989 mazda rx7 gtu with a 13b rotary... i can not get it to start.. i can get it to crank over
but i cant get it to start completely.. so i was just checking around and just jumped it to see if that was
the problem it started easier but still hard to crank over i am not for sure on what is wrong with it... and
then i am having problems with it idling and not for sure if the throttle sensor is bad and i dont want to
go out and buy a new one and have the same problem.... Can anyone help?
15 Answers
Have you checked your Fuel Filter? You can check it by taking it off, and blowing through it, mostly all clean looking gas should come out, but if it comes out dirty that might be your problem, and you can replace it, but i have heard that some of them you can clean.
i thought fuel filter was in the gas tank?? that might be a challenge to get out if it is... but then that wouldnt explain why its easier to start it if i jump it though...
Does it spin up normally when you push dowsn on the throttle? Does the idle stability improve when the engine warms up? Do the exhaust gases smell rich? Is the TPS adjusted correctly? Is the ignition timing set correctly? There's just a bit too much info missing to get to a proper diagnosis. It could be a vacuum leak or a million other causes and without more info it's hard to narrow it down to a single system, let alone a component...
once the car is running it runs fine other than it has no get up and go once you step on the throttle.. how do you adjust the tps? im new to the rotary world and dont know much about it... and you can sit there and hold the key for like 5 minutes and alls it does is just crank over i cant get it to start up... and the idle with not stay consistant it will die down and then it revs back up it will constantly do that the whole time... i cant figure it out... but i cant get it to turn over by its self but once i jump it it will start up... the exhaust fumes arent to bad but it will smoke alot for about 10 minutes after i start it up...
In that case start by getting a copy of the FSM at http://www.rotaryheads.com/PDF/2nd_gen To me it sounds a like there's more than one thing going wrong, you might want to start with checking the fuel pressure and looking for vacuum leaks. You might find the information on the FC3SPro site useful too: http://fc3spro.com/main.html
how do you check the fuel pressure? and i will look for leaks...thank you!!
The comprehensive fuel pressure test is as follows. Release fuel pressure by disconnecting power cable going to the fuel pump while the engine is running, wait for the engine to stall due to fuel starvation, turn off the ignition and reconnect power to the fuel pump. Connect a fuel pressure gauge using a T-connector and a piece of fuel hose between the feed hose and the fuel rail (make sure to use hose clamps to prevent spillage). Then prime the fuel system by using a jumper wire between the two contacts on the yellow connector on the right hand front strut tower, turn the ignition on and read the pressure gauge. Pressure should be between 34 and 40 psi. If it's low, start by checking for leaks, then replacing the fuel filter and test again. If that doesn't rectify the low fuel pressure condition test the fuel pump pressure and pressure regulator. If the pressure is too high, it's definitely the fuel pressure regulator. Turn off the ignition and wait 5 minutes then read the gauge again, pressure should be above 18psi, if this is not the case you will need to check the fuel pump or you have injector leakage. To check the fuel pump you will need to connect the gauge straight to the outgoing hose from the fuel filter (no T-connector and make sure you release the pressure off the system first) then turn the ignition on for about 10 seconds then read the gauge, pressure should be between 71 and 93psi, if it's outside these values the pump should be replaced. Next turn the ignition off and wait for 5 minutes before reading the gauge again, pressure should be above 57 psi, if not, replace the pump. Carefully release the fuel pressure, remove the pressure gauge and reconnect the hose to the fuel rail. Then prime the fuel system by turning on the ignition for 10 seconds and remove the jumper wire.
Thank you i will look into this one and get back you!!
texturboII answered 11 years ago
Probably flooded. Remove the EGI fuse from the fuse box near the driver side shock tower. Crank the car over for about 5 seconds. Replace the fuse and try to start. Also, a common problem with these cars in regards to Fuel Pressure is faulty / old wiring to the pump. It is recommended to re-wire the fuel pump in order to get the best performance from it.
Was wondering if you figured out the problem with gtu. My 90 rx7 does some of things the guy in the suit was asking. Idle gets better after it warms up and is burning rich smell from exhaust, but one thing that really annoying is when pulling up to a stop light or sign and I pop out of gear my rpms drop to pretty much 0. Not sure why.
My rx-7 fd3s also idling super rich now I take a injector go to check ! Many rx-7 have this problem why also cannot settle?
hey,all wrong answers.what you have to do is remove all plugs ,crank the engine too remove the petrol in the cyclinders,then add a small amount of engine oil into the cyclinders,put back all the plugs,,and wallagh,,,your engine will fire up and purr like a kitten,works and you do not need a fuel pump,OK
the above answer is correct - i recommend transmission fluid instead of oil. beware - it will produce a lot of smoke out of the tail pipe and make sure the battery is fully charged, you might have to crank the engine for several seconds. This was called "Short Start" back int he early 90's
Here is the procedure in full RX 7 detail. https://www.rx7.com/techarticles_unfloodFC.html And - No - this is not a joke. This service is even performed at Mazda Dealerships.
1989 mazda rx 7, turned over when first received it. Turn over for a couple of seconds. stopped as the fuel system was clogged up from sitting 21 years. Anybody have a wiring diagram of starting system or location of any starting relays?
