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Guest BigErn

Sluggish Mi16

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Guest BigErn

Right bear with me Im new :)

 

I have had a go with the search option and not found much Im looking for so thought Id ask.

 

I have recently bought a 205 with (1.9)Mi16 engine, running the 405 management too. And when driving it it seems a bit on the sluggish side, Through the first 3 gears its not overly bad but lacks any good strong pull. Come 4th and 5th it seems to take forever to get the revs up, especially 5th. As a comparison my mates C20XE Mk3 Astra walks all over it when side by side.

 

Has anyone experienced similar problems or any ideas why it could be like this? My initial thoughts are possibly air flow meter related or throttle sensor, does this sound viable? I am a total Pug virgin (bar the XUD Citroen ZX I have with pump and boost turned up, lol) so any checks I need to do can you also explain how to do them.

 

Thanks in advance :P

 

Ian

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dcc

Does she use more fuel than she should?

 

I would hesitate a guess at something timing related, maybe an exhaust cam a tooth out?

 

AFM dont normally give that sort of effect on the engine.

 

Might be worth testing the water for traces of oil. posible HG ?

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dcc

forgot to mention:

 

Possible dead fuel pump

Injector issues

Low fuel pressure (FPR)

do these run with Lambda's? (cant remember :|)

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jackherer

Could be something fueling related, most likely the airflow meter. Does it rev cleanly or misfire? Does it smoke?

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jackherer
AFM dont normally give that sort of effect on the engine.

 

They definitely can, I've had 'slow' afms in my collection, I once used one on a mates car that I built as I felt he was a bit out of control...

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GLPoomobile

When I bought my Mi I felt it was a bit disappointly slow. On a private test rack (aren't they always?) it couldn't break 120 (and this is on a 1.6 'box) so I knew something was up. Sometime later I had problems with it idling really badly and stalling in traffic. The day after it wouldn't run at all and I traced it to the AFM. The flap was jammed wide open. After releasing it, the spring was f***ed and had no tension to it.

 

With a replacement AFM it was much better and felt as quick as I hoped it would be, and now will pull cleanly past 120 and on to 130+ (I've never had it topped out yet though).

 

It could of course be something else, but the AFM shouldn't be ruled out.

Edited by GLPoomobile

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Guest BigErn

Thanks for the replies so far guys.

 

To answer the questions.....

 

There is no smoke from her at all. The engine is sweet and has covered 120k. The chap who put it in the 205 also owned the 405 the motor came from and wrote down the mileage of the engine and the mileage of the 205 when he did the conversion. I also have the history for the 405.

There is no oil and water mixing. No visable signs anyway.

Seems to be ok on fuel (Im used to running a M5 though). As a guage it used roughly £20-25 of fuel to do the 180 mile trip home when I collected it.

 

GLPoomobile - Mine is ok ish to about 100 then after that it takes forever and a day to get any faster, like yours it really really struggles to crack 120.

 

Another question, is the 1.9Gti Airflow meter the same as the Mi16 unit??

 

Thanks so far guys :lol:

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pug309twin40s

1.6/1.9 8v afm, isnt the same, apart from the late 1.9 cat engines which use the same afm's.

 

have you checked the condition of the plugs, leads, rotor arm and cap?

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DrSarty

Whip the plugs out and see how it's fuelling. As you perhaps know, you're wanting to see light brown, fawn coloured deposits. This is a good place to start.

 

Then a comp test wouldn't be a bad idea; then if all the above looks good, you need to do one-for-one swaps of things with a test drive in between to see what gives.

 

I suspect fuelling somehow, as a spark is usually a spark; so I wouldn't expect it to be a weak coil, amp or HT lead as that would probably give obvious missing rather than low power.

 

Another outside chance is a collapsed exhaust section, such as mid or rear, which could have baffles blocking the gases and choking the engine.

 

It's a painful process of elimination I'm afraid.

 

I had this recently, and it was tracked down to a bodged join in a fuel pump immobilisor circuit someone had put in and then removed, badly. :lol:

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Guest BigErn

I havent checked the plugs or ignition stuff yet as its now snowing outside. Bored of the white stuff now, stroll on summer :lol:

 

My thought would be more fuelling related for this problem tbh, as DrSarty says if it was ignition related it would more likely be a missfire caused by something breaking down under load. However Im not totally ruling it out and may well change them myself just for piece of mind.

Ive had a glimpse under it and its running the 405 exhaust manifold, what looks like a standard Gti centre pipe with box chopped out and same diameter pipe welded in and its on a standard Gti back box. Im thinking its a possibility the standard back box isnt helping and may be struggling to let the engine breathe properly.

 

Is it worth rewiring the fuel pump on these cars? Cosworths are notorious for being low voltage at the pump on the standard tired wiring now, not a good thing for the fuel delivery to big power expensive engines.

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Guest BigErn

Also how do I test the airflow meter? At the ecu? Running? Ignition on only? What pins? Its a M1.3 3 row ecu.

 

Thanks peeps :lol:

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kyepan
Also how do I test the airflow meter? At the ecu? Running? Ignition on only? What pins? Its a M1.3 3 row ecu.

 

Thanks peeps :)

Firstly..... i tried to post yesterday from my phone, but the post was lost.

 

I'm gonna be a bit contrary and say i don't think it's any of the above.

 

The reason being, is i have had something very similar, My Mi also felt flat, it went ok at the bottom but when it was supposed to get charging, it didn't, and the top end was not very "top"..

 

My battery terminals and earthing were to blame, earths have already been mentioned but not terminals.

 

On my negative terminal, i had a screw on cap type, even though it was on tight, the cap was not making enough contact with the replacement battery i had put in. It had also been on and off so many times that the plastic thread barely had any bite.

 

Secondly the positive was knackered... all of this added up to clicky starter solonoid issues and one very sluggish MI16.

 

If either your positive or negatives are not on absolutely right and tight, with enough surface area to transfer buckets of current then you may be suffering the same thing. By tight i mean that you cannot move them by hand, or pull them off.

 

Needless to say, replacing the negative terminal and screwing the positive down hard fixed this, the car felt brighter and back to life.

 

to answer your other questions.

 

To test the AFM you need to get a copy of caps, and install it, that will give you the volt meter readings, and resistance ranges, it will take 10 mins and a volt meter. You can test the afm off car by measuring reistance, and on car by back probing the connector block to test the voltage, the wires should be numbered in your haynes, and in caps. The pins as i understand it are the same on the afm, whether it is two or 3 row.

 

Best of luck.

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Anthony
Also how do I test the airflow meter? At the ecu? Running? Ignition on only? What pins? Its a M1.3 3 row ecu.

If it's a 3-row ECU, check that the knock sensor is present and connected

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kyepan
If it's a 3-row ECU, check that the knock sensor is present and connected

good point, i had one go on my pulsar, and it was very down on power as the ignition went into super retarded limp home mode.

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Guest BigErn

Cool, Ill have a look at that too. Where abouts does it live on these engines?

 

I had a go a re tracking my AFM today too as well as fitting some new plugs and cleaning up the dizzy cap and rotor arm and it seems sweeter and has a bit more pull and throttle response at lower revs. I havent as yet checked the AFM readings but from feel alone it seems to have improved the car a bit.

 

Something else I have now considered is the fact I may well be over expecting from the car, so to speak. For the past 5 years I have owned Cosworths and also currently own an E39 M5 so Im wondering if Im comparing the power delivery too much and expecting more than the Mi can give. Are there any videos of Mi'd 205's going round the speedo so I can roughly compare..... It may just be me thats the problem and not the car ;)

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DrSarty

The knock sensor lives on the front of the block, centrally and just above the oil filler hose connection.

 

It's often green in colour with a bracket holding the connector.

 

It's bolted to the block through its centre, and is effectively 'listening' for det. It has Piezo crystals inside which vibrates at certain frequencies (when it hears pre-ignition) and generates a current/voltage which the ECU receives and retards the ignition.

 

This is why if it's FUBAR or reading incorrectly, as Anthony suggested, it is either over retarding the ignition or switching to a limp home/safe mode. This massive retardation could be what's killing the power.

 

On the other hand, the other car comparisons you are making could be the reason, although a Mi 205 is pretty darn rapid. They will keep up with a Cosworth on track, mainly the twisties, but then the extra horses of the Ford will see it pull away on straights usually. An M5's a different kettle of fish.

Edited by DrSarty

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kyepan
It may just be me thats the problem and not the car :huh:

on a 1.6 box, a healthy mi should pull past 100 cleanly and pretty much on to the redline in fifth without really slowing down.

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dcc

Oh, just thinking, when you give it full throttle, do both butterflys open fully?

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Guest BigErn

Yes Ive had the pipe off and pulled the cable, both butterflys open up. Are they supposed to open one then the other or simultaneously?

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Guest BigErn

Been out playing today and have noticed it seems to be a fairly long legged box on it. It does almost 70 in 2nd, 92 in 3rd and 110 in 4th. I was told it was the 1.9Gti gearbox, is this about right? Are there numbers on the box to identify whats in it?

 

Also have checked the fuel pressure today too, when I pulled the pipe off the rail there didnt seem to be alot of pressure there. But by the guage (MAC tools) it was running 3bar at full throttle (vac pipe off) when running.

 

 

Cheers, folks.

Edited by BigErn

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kyepan

that sounds right, have you had it under load at full throttle with the gauge on?

 

also what are the battery terminals like (like a broken record me)

 

J

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Guest BigErn

No mate, never took it out and drove it with guage on. Just removed vac pipe to get the full throttle reading. Battery terminals are both bolt on jobs, not the old plastic screw on terminals. I am however going to give them a good clean up tomorrow and also do the earths too, just to be sure.

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JRL

Hi mate. my mi was running slow it was rebuilt thought i had bought a dud. it seem to rev up well but didnt pull at all well. I spent ages on the afm and emissions tuning and then finally before i was nearly going to get rid I swapped the gearbox for an mi16 as I was told without the 4.4 crown wheel pinion (cwp) it will lack power. Once fitted the power was bang on! but check everything else before you start ripping out the gearbox.

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richsmells

Surely the gearbox has no effect on the power output of an engine, only the delivery?

Edited by richsmells

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welshpug

The poor delivery from an awful set of gear ratios will make them seem very sluggish, Pugtop had this issue with a box fitted to his rally car.

 

Came from a 1.6 carb 405, massive gaps between 3rd 4th and 5th, would struggle to pull 120 and was nowhere near the limiter, now with a 1.6 cluster and 4.4 Mi16 F/D it nuts the limiter at 125 :lol:

 

 

certainly possible and worth checking it is a decent box in there, not a random.

 

easy to check though, what RPM is it at 70 mph in 5th?

Edited by welshpug

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