Would really appreciate some advice..
I drove my car 250 miles to Birmingham today, without a problem. I then parked in an indoor car park. When I left the car park, the following problem developed:
10% of the time - no problem, car seems to drive ok, perhaps a little "lacking".
90% of the time, it idles very low, and also only revs to a maximum of 4000rpm at which point it begins to backfire popping and banging, making it difficult to drive about 10mph.
Any idea what this is? I am meant to drive 250 miles home tomorrow, and am currently facing the prospect of having to leave the car in birmingham and get the train back
I\'m not in the AA
It was raining quite heavy today.
The car has done about 40,000 miles, 1994, mechanically standard.
Any help would be much appreciated.
Cheers
erm i no nothing guessing it might be in limp mode or sumin try resetting ECU, er sumin like disconnect battery & pump brake a load of times? Anyone with knowledge wana comment.....?
Si
mine does that, but its because i have a exhaust that looks like its been infested with rats (basicaly lots of holes in it), on cold start it idles around 5000, when the car is hot enough, it gets back up to normal idling revs, but will be popping once in a whilewith the revs dropping a few 100s,
and when it is cold, when i stop for lights or whatever it often stalls itself, so i dont know if this is the same problem you are experiencing, by the way mine is a FC
Pat
I take it you meant 500, not 5000 revs... in which case the problem sounds quite similar. However, the low idling isn\'t really my main problem, its the fact that I can\'t take it above 4000rpm as it seems to "cut out" at this point, backfiring. Also, in the rev range up to 4000rpm, there seems to be much less power than there should be.
The exhaust is a good point. Mine is a mazdaspeed item, and is slightly damaged underneath due to the car being low. But the exhaust sustained no extra damage before the car began to show this problem, so I don\'t think this is the cause.
I\'m not a mechanic but I\'m *hoping* its something like spark plugs or leads??
check there hose is on the map sensor.
Passenger side on fire wall small black plastic box 1x2 cm.
well, i am not too much of an expert, but i am hazarding a guess that it may be the ecu or your second turbo??? :confused:
if it does not deliver at around 4000revs then thats near to when your second turbo kicks in, so maybe its that that is the problem?? or it could be the ecu not allowing it to go any further for some reason?
at one point my car wouldnt go over 0.3bar of boost because when i fitted the boost controller i didnt remove the standard boost solnoid valve, so i guessed that the ecu limited me to 0.3bar as a precautionary measure???
my point is, maybe there is something wrong witht the second turbo and the ecu has picked that up therefore holding the car back?? but the popping and backfiring sounds like a rusty exhaust to me,
I\'ve just come back from checking it again - it now does it 100% of the time, and cuts out as follows:
4000rpm in 1st gear
c.3000rpm in 2nd gear
and lower in 3rd
So it does seem as though the ECU is limiting boost..? Anyway I\'ll check the hose is on the map sensor and report back
Thanks a lot for your replies so far, its really appreciated!!
I have the same problem i was just about to post a new thread about it aswell!!!!...i just managed to start my car finally this evening, after 4 weeks of sitting in the drive. it idles and revs fine but when in gear and actually driving it cuts out at 3k-4k revs and backfires/heavy poping like gunshots scares shit outa people including me!! sounds really dangerous to the engine i thought it might be the restricter or something, i reset the ecu took the battery off etc. im using a 20amp fuse instead of a 30amp in the small fuse box next to the battery ill check which one in the morning, because when it was stolen the thieves pulled all the fuses out and no1 had any 40amp fuses today when i went to buy one. but its the same as yours luciano as soon as you put ur foot down it fires and pops but doesnt move! if you mildly accl then you can go through the rev range but u put ur foot down half way and it fires/pops!!! Gary what were u refering to? the fuse box i mentioned? could it be the fuse? ill get the propper fuses on monday see if it makes any difference. ill try resetting and changing fuses around etc tmrw morning.
"check hose is on map sensor"??? plz can ou take a pic so i know what to look for...
Rixio:wave
Use the diagnostic socket bud. i cant remember which pins it is but you can put a led between em and if you count the flashes you can relate it to a fault code. there is a list somewhere on the net. i can get one if need be but not straight away
scott
somebody on here must know
I\'ve checked the hose on the MAP sensor and its connected correctly.
Rixio, if you need a picture go to http://www.iluvmyrx7.com/ select Gen 3 Manual and then Fuel and Emmission control systems. Its on page F167.
I\'ll have to read the fault code tomorrow. I\'m a bit worried that if I don\'t get it sorted by tomorrow afternoon I\'ll have to leave it here in Birmingham and catch the train back to newcastle. :(
I know this dont help much mate but tow it home. dont leave it there. I think there should be a calling all rex owners in bham help post...
scott
Its not so bad leaving it in Birmingham, my girlfriend lives there so it should be relatively safe.
The annoying thing is that it\'ll take longer and be more difficult to repair the problem when the car is so far from where I live!
Its life I guess. I\'ll read the fault code tomorrow and see if that helps.
Incidentally, if the engine management light isn\'t on, shouldn\'t that indicate that the ECU hasn\'t got any fault codes stored inside?
the ecu light comes on only when its registered a fault and logged it yes so theres no prob there...i actually just remebered that my abs light is on aswell dono why any ideas??
rixio:wave
My last attempt.
have you tried letting the car fully warm up before moving it. if the engine temp sensor is dead it will go in to limp mode but you might stand a chance if it warms up fully first.. dunno for defo just trying to give you ideas. sorry mate
scott:mad:
Not sure whether it\'s the same problem, but might be worth considering. Mine has an intermittent problem that\'s a little like this. It will start up normally, usual idle, but cuts out as you apply more throttle. I haven\'t pushed it too far past the cut out point so I don\'t know whether it backfires under harder throttle. If you have a boost guage, it runs fine to about 200 mm/hg but above that it goes slightly "fluffy" and then cuts out. The ECU light does not come on.
I\'m still chasing the fault, but it goes away when I try to trace it.
Simple way to get it to run again - remove one hose from the pressure tank (under the strut brace) to vent the pressure. Remove the hoses from the small green and white check valves under the mainfold next to the pressure tank to vent the vacuum. Put it back together. Important! - now leave it for 4 hours. After that it normally runs perfectly again for a few weeks before breaking again.
I think that mine is due to a sticking solonoid in the solonoid pack under the manifold because the vacuum to the charge control valve drops when the fault appears. Unfortunately, taking it apart fixes it, so I haven\'t found which one it is yet!
Rgds
Keith
I think the valves you speak of are pcv valves. i think im correct in saying if they stick open they are a problem but if they stick shut it dont matter. They are normally closed when the car is off idle. you maybe correct in what you say. if they are stuck open you will continue to get a zorst recirculation at higher rpm.
scott
Sounds like the car is in "Limp Mode" for sure,if you rev the car real gentle it will pick up to around 4000rpm but if you rev hard it holds back,sounds powerless up till 4000rpm??????????.When you get a fault and the ecu doesnt receive the correct readings/figures it will go into limp mode.Basically it is fixing the timing and fuelling at set amount for you to be able to "limp" the car home.You can try removing the earth off the battery and sit with the brake pedal depressed for 10 minutes, this will clear the ecu of any fault codes.If the car runs ok after then it was or is an intermitent fault,if it is the same then you have got a problem.
Do all your gauges work,read correctly?Have a quick look over engine to make sure all connectors,pipes are going somewhere,none hanging lose or not connected.
Hope this helps.
Gary
none of the hoses or anything are dissconnected on mine im gona try the brake thing to reset the ecu now but is this the correct way to reset the ecu?(never heard of it before) if it still does it after what does that mean?? anyway ill repot back when iv tried the brake thing...luciano u had any luck m8y??
rixio
The brake thing is only needed to be done for 10 seconds(I Think that is what Gary meant),it completely drains all power from the ECU if the battery is disconected first.
When power is reconnected the ECU should revert back to normal operating provided there is nothing else wrong.
Kind regards
Carl
so i sat there in the car for 15 minutes when i coulda done it for 15 seconds!!!! omg!!! anyways IT WORKED!!!
ITS ALIVE ITS ALIIIIIVE
THX FOR UR HELP DUDES COULDNT HAVE DONE IT WITHOUT U!!!
now iv got put all the dash back on!! ack!!!
rixio:wave
I will try resetting the ECU now, but I\'m a little worried for two reasons:
1) Presumably the car went into limp-home mode for a reason? Is it okay to carry on driving before I\'ve found out why?
2) What if it happens again somewhere between Birmingham and Newcastle!
Anyway I\'ll go and reset it now and see how the car runs.
Thanks again
I reset it, drove the car up the road - everything was okay, but then at the end of the road the car went back into limp home mode again.
So its now the same as before.
When the car was running normally just now, it did still backfire a little when you took your foot off the accellerator, not sure if that gives any indication of whats wrong?
I think I\'ll try and read the fault code now..
how long did u keep braking for?? i spent a good 15 mins on it so it might be that dono but if it only takes 10-15sec then sry no can help...try asking a local mechanic otherwise im fresh out of ideas...sry m8. hopefully ull sort it though
rixio:wave
QuoteOriginally posted by Luciano
When the car was running normally just now, it did still backfire a little when you took your foot off the accellerator, not sure if that gives any indication of whats wrong?
Think thats normal when they are first started, at least i hope it is as mine does it for the first couple of mins, till it starts to warm up.
Other than that sorry i have no idea, :( hope you get it sorted ASAP.
Mark
The two things that put it in limp home mode are the charge control and oil metering pump.
You can check the charge control actuator by turning the ignition on or starting the car it should get pulled in when you do this, the actuator is the small one on top of the Y pipe.
Also check the crank angle sensors, give them a clean if dirty.
Jason
Yes check crank angle sensor connections,had that problem myself although it tends to stop car from starting,wont even fire.
Oil metering pump connector is another good place to check,look in front of oil filler neck you will see lifting eyelit.On the side of that is a big plug connector approx 8-12 wires.Pull plug apart and clean connections with switch cleaner,if not brake cleaner or plug that goes onto metering pump itself bottom left front corner of block just below front turbo oil return.If return is leaking it will oil up connector causing a resistance.
On the back of water housing is a single wire sensor for water temp to ecu,check that also.
How long did you drive it for,any particular moment it started to happen.e.g - just off cold start,same amount of time everytime from starting to problem arising????Could help in finding the problem,as much info as poss.
QuoteOriginally posted by K1HKS arse
Yes check crank angle sensor connections,had that problem myself although it tends to stop car from starting,wont even fire.
Oil metering pump connector is another good place to check,look in front of oil filler neck you will see lifting eyelit.On the side of that is a big plug connector approx 8-12 wires.Pull plug apart and clean connections with switch cleaner,if not brake cleaner or plug that goes onto metering pump itself bottom left front corner of block just below front turbo oil return.If return is leaking it will oil up connector causing a resistance.
On the back of water housing is a single wire sensor for water temp to ecu,check that also.
How long did you drive it for,any particular moment it started to happen.e.g - just off cold start,same amount of time everytime from starting to problem arising????Could help in finding the problem,as much info as poss.
Nice write up, you like typing more than me!:rollin
I think one of these should sort his problem.
Just like to help out if possible? If it fixings problem its nice to know i have helped a fellow enthusiast and that i have actually learnt something about rex\'s in 4 years!!!!!!!!!!!!!!!!!!!
Just to confirm:
When I start the car, approximately 70% of the time it goes immediately into limp home mode. the other 30% of the time, it drives fine for 100 metres, and then goes into limp home mode.
I have now left the car behind, and I\'m back in Newcastle now... :(
Thanks a lot for all the suggestions - keep them coming. When I go back to the car (probably in a week or so) I\'ll have a list of things I can try - all thanks to you guys... so cheers.
If the suggestions from this thread don\'t work, I\'m going to take it to a specialist..
Will update you when I\'m back with the car and have tried out the things mentioned above.
Thanks again!
The cat on the car may have collapsed! happened on my rx when i first got it totallt restricted the running of the car and sorted after, also check this; If you look at the engine just before the inlet manifold a small black box in the middle of the engine take that off and check the two small hoses are connected this again happened on my rx and meant that car drove fine until it was time for the second turbo to take over! Dont know if it will help but good luck anyway! there is nothing worse than a car running poorly!!!!
RAC membership, cheap as chips and well worth getting
Buy RAC membership, next day have car towed to garage
problem solved
very tru very tru
spot on if you need it...personaly imo RAC is w*nk id go with the AA instead
rixio:wave
**Update**
Went back to the car with my dad (a mechanic) 3 weeks after I left it outside in limp home mode.
Turned the key, started first time.
Dad wanted to see how far it drove before going into limp home mode, so I drove it around... and it kept driving!
Have now done just over 500 miles since that point. Hasn\'t failed me yet.
Worried it will fail, so just spent £120 on AA cover...! I drive Newcastle to London regularly, so it makes sense...
Thanks for all your help
QuoteOriginally posted by davefrith
RAC membership, cheap as chips and well worth getting
Buy RAC membership, next day have car towed to garage
problem solved
Dave\'s right, l found is that if you have home start and your car needs to go to a garage because it won\'t go, they will transport it for you FOC, to the garage of your choice even if it is miles away.
You also get it even cheaper by being an MRC member on production of your membership number due to schemes the club has with both the RAC and the AA