new chim no running well, where to start ??
Discussion
Hi guys, theres now some definate running problems with my 430, but think I need to establish a sensible way forward before I hand over to the experts. E.g things I can rule out first and really assess the health of the engine.
Heres some info on the car: its a 93 430, only 42k on the clock, before my ownership, went through long phases of not been driven, less than 10 miles some years.
It runs very very roughly at idle - some friends that also have chims confirm it is not healthy.
The car has had some changes in the past that I cant properly confirm. Aparantly it was running lean so another chip was fitted along with a switch for another tune resistor to allow changing between non and cat fuel maps. It was a torque V8 chip.
So when I bought it, it was running this 5.0 chip I suspect on a non-cat map. It went reasonably well perf wise. was very thirsty though even on a cruise.
I have now serviced it, changed the stat as it was running cold all the time, cleaned the stepper also.
I have also changed the chip back to the std one i was given with the car (cant really confirm it is). It is now down on power and the plugs are still sooty black - as per my other thread - re injector spray pattern?
When i run it on the cat fuel map - things get evern worse - idle is far worse, and it hesitates and misses when coming on throttle and is further down on power.
I suspect these fueling changes were to hide an underlaying issue, but where to start to get some baseline data.??
Ive read some posts on the cats being damaged and possibly melting with cars with over fueling, so that could be a potential here?
My rev counter has also started to bounce and fluctuate badly, so I am assuming the ECU wont be getting a great RPS signal now either?
Could the injectors be tom blame for a lot of this? the rest of the engine is stock.
The biggest issue i suppose is that i cant guarentee that the chip i was given was definately a std 430 chip.
Any suggestions to a plan moving forward would be greatly aprpeciated.
Best regards
Heres some info on the car: its a 93 430, only 42k on the clock, before my ownership, went through long phases of not been driven, less than 10 miles some years.
It runs very very roughly at idle - some friends that also have chims confirm it is not healthy.
The car has had some changes in the past that I cant properly confirm. Aparantly it was running lean so another chip was fitted along with a switch for another tune resistor to allow changing between non and cat fuel maps. It was a torque V8 chip.
So when I bought it, it was running this 5.0 chip I suspect on a non-cat map. It went reasonably well perf wise. was very thirsty though even on a cruise.
I have now serviced it, changed the stat as it was running cold all the time, cleaned the stepper also.
I have also changed the chip back to the std one i was given with the car (cant really confirm it is). It is now down on power and the plugs are still sooty black - as per my other thread - re injector spray pattern?
When i run it on the cat fuel map - things get evern worse - idle is far worse, and it hesitates and misses when coming on throttle and is further down on power.
I suspect these fueling changes were to hide an underlaying issue, but where to start to get some baseline data.??
Ive read some posts on the cats being damaged and possibly melting with cars with over fueling, so that could be a potential here?
My rev counter has also started to bounce and fluctuate badly, so I am assuming the ECU wont be getting a great RPS signal now either?
Could the injectors be tom blame for a lot of this? the rest of the engine is stock.
The biggest issue i suppose is that i cant guarentee that the chip i was given was definately a std 430 chip.
Any suggestions to a plan moving forward would be greatly aprpeciated.
Best regards
If some one fitted the Torque V8 chip, what other modifications may have been done?- One I looked at had an extra fuel pressure regulator fitted ontop of the origional to boost the fuel pressure, but no way of controling the fuel prssure from the plenum vaccum- so it was overfueling the car really bady- It was a bodge factor 10 out of 10 to try and get the fuelling right with the Torquev8 AFM. On top of this the stepper was not working correctly, so a plumbers gate valve had been installed to control the airflow- Anyone who has been of this forum for a while will know what I think of the TorqueV8 product......
So check-
Is the fuel pressure regulator stock- is its vacume pipe connected?
Is the AFM wiring still intact?. I assume it no longer has the Torque V8 AFM fitted.
If the engine has been run on a non catalysts fuel map, and it has catalysts fitted it could have melted the precats and blocked the exhaust downtubes or damaged the main cat.
Spend the £110 to get a Steve heath ECUmate and have a look at the sensor data, in particular the lambda probe outputs, so you can see really whats going on. It will also tell you what fuel map its running- it may be in fall back mode and you wont know- guesswork and swapping parts is not a good diagnostic approach.
So check-
Is the fuel pressure regulator stock- is its vacume pipe connected?
Is the AFM wiring still intact?. I assume it no longer has the Torque V8 AFM fitted.
If the engine has been run on a non catalysts fuel map, and it has catalysts fitted it could have melted the precats and blocked the exhaust downtubes or damaged the main cat.
Spend the £110 to get a Steve heath ECUmate and have a look at the sensor data, in particular the lambda probe outputs, so you can see really whats going on. It will also tell you what fuel map its running- it may be in fall back mode and you wont know- guesswork and swapping parts is not a good diagnostic approach.
Hi there, there appears to be no other mods done to it except the chip. std fuel pressure reg and AFM - i will take some pics tonight to confirm.
The afm wiring looks sounds fine to me, the plug isnt corroded and fits well.
i was going to take the pre cats out at some point. Im assuming the only way to inspect the main cat is using one of those cameras on a flexible extension once the downipipe is off?
The afm wiring looks sounds fine to me, the plug isnt corroded and fits well.
i was going to take the pre cats out at some point. Im assuming the only way to inspect the main cat is using one of those cameras on a flexible extension once the downipipe is off?
I would be checking the camshaft on a Rover V8 that has only done 40k in 19 years & has had long periods of inactivity.
Cam wear is very common on these engines and the hydraulic lifters hide the wear well.
The cam suffers most wear on the first start-up after a long period of inactivity, this is because the oil film on the lobes will have been lost over time.
The camshaft is the heart of your engine, if it's badly worn the valves won't be opening fully so you will never get proper combustion.
You can fiddle with the fuelling all you like, if the cam is badly worn it will never run well.
Also use a strobe to check & adjust your ignition timing and make sure the distributor is advancing correctly.
A full ignition service including a new genuine rotor arm, dizy cap, plugs & leads is also advisable if you haven't done so already.
Once you are confident your valves are opening correctly and the ignition side is in tip top condition you can then start to look at the fuelling.
A good place to start would be to ensure the fuel pressure is correct.
Try and keep to standard components (fuel pressure regulator & chip).
Stick to the standard settings (ignition timing & fuel pressure).
Throw away any misguided attempts at tuning like non-original ECU chips, incorrect tune resistors, or adjustable rising rate fuel pressure regulator.
As a starting point you are looking to get the mechanical, ignition & fuelling elements back to as close to original as you can.
Good luck & let us know how you get on.
Cam wear is very common on these engines and the hydraulic lifters hide the wear well.
The cam suffers most wear on the first start-up after a long period of inactivity, this is because the oil film on the lobes will have been lost over time.
The camshaft is the heart of your engine, if it's badly worn the valves won't be opening fully so you will never get proper combustion.
You can fiddle with the fuelling all you like, if the cam is badly worn it will never run well.
Also use a strobe to check & adjust your ignition timing and make sure the distributor is advancing correctly.
A full ignition service including a new genuine rotor arm, dizy cap, plugs & leads is also advisable if you haven't done so already.
Once you are confident your valves are opening correctly and the ignition side is in tip top condition you can then start to look at the fuelling.
A good place to start would be to ensure the fuel pressure is correct.
Try and keep to standard components (fuel pressure regulator & chip).
Stick to the standard settings (ignition timing & fuel pressure).
Throw away any misguided attempts at tuning like non-original ECU chips, incorrect tune resistors, or adjustable rising rate fuel pressure regulator.
As a starting point you are looking to get the mechanical, ignition & fuelling elements back to as close to original as you can.
Good luck & let us know how you get on.
The advice about the cam and getting things standard is good, but I would not start with the ECU' they dont fail that often compared to things like the AFM that gets cooked. This is why Im a great believer in getting some decent test readings and doing things step by step. The ECUmate makes things a lot easier, or you can get freeware that allows you to read data from the ECU via a laptop with the correct cable. Obviously using a laptop is not ideal for road testing unless you can put it on a passengers lap.
http://www.pistonheads.com/gassing/topic.asp?t=113...
These diagnostics only cover the ECU and sensors, and wont pick up a worn cam. Severe failing HT shows up as lean lambda readings as unburnt mixture looks like a lean mixture to a lambda probe.
http://www.pistonheads.com/gassing/topic.asp?t=113...
These diagnostics only cover the ECU and sensors, and wont pick up a worn cam. Severe failing HT shows up as lean lambda readings as unburnt mixture looks like a lean mixture to a lambda probe.
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