Technical Need Croma Wiring Diagrams

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Technical Need Croma Wiring Diagrams

croma4ever

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Feb 15, 2021
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Hi all,
We have a Fiat Croma 2.0 ie which was bought from new. Is there any chance that you have any Wiring Diagrams (namely, Engine, Ignition, ECU, etc.) for it?

Here are the details:

1987 Fiat Croma 2.0 ie (super version) Ignition and Fuel Injection Weber

(It must be the Weber system, as opposed to the more popular BOSCH)

Problem - The cold start is terrible and when it does eventually start, the throttle needs to be feathered for a few minutes until the engine warms up, otherwise it will stall……. Then, it will maintain tick-over. When driving, the engine just lacks power and if you try to accelerate more the engine just ‘chocks-up’ and the speed drops. Easing off the accelerator allows for the car to pick up but the acceleration is just so slow…… Once, I hit a slight bump in the road and the engine went dead…. Fortunately, the motion of starting the engine allowed for a reconnection and the engine started. Therefore, there seems to be a connection problem somewhere down the line.

(I have visited your Forum and found an owner posting a message with EXACTLY the same issue! The response was that it could be a loose connector or broken wire. The problem for our mechanic is that without a wiring diagram it is near impossible to solve. If he has a plan, then he will know what wire goes where and can pass an electrical current through it in order to test it. The ‘Earth’ is good, by the way)

New parts – ECU, Distributor, Temperature Sensor, Connection Block for Coil.

Result – No resolve but the car is far more efficient in terms of fuel…..


Any help much appreciated!


Thanks
 
Hi all,
We have a Fiat Croma 2.0 ie which was bought from new. Is there any chance that you have any Wiring Diagrams (namely, Engine, Ignition, ECU, etc.) for it?

Here are the details:

1987 Fiat Croma 2.0 ie (super version) Ignition and Fuel Injection Weber

(It must be the Weber system, as opposed to the more popular BOSCH)

These are from the original Fiat workshop manual.
.
 

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Hi there,
Thanks so much for finding them for me! Hopefully our mechanic will be able to get our Croma to purr like a kitten again.


It is not much fun driving around in a ‘crippled Croma’……

:)
 
Hi there,
Could you please send me the ‘Component Key’ (On page 33 of the photocopied Diagram that you sent me, it refers to page 37).

Also, does a page exist that illustrates the colours of the wiring?

Just to recap, it is for a 1987 Fiat Croma 2.0 ie (super version) Weber system


Thanks for your continued support…..
 
Hi Davren,
Thanks very much for going to the trouble. Where would FIAT owners be without your help?!!!!!!

(Kudos to the FIAT owner of the X1/9 whom I met by chance, when filling our car with petrol about 8 years ago, at our local petrol station…… I was discussing the problem with finding spare parts and he recommended the FIAT Forum…...)


Your site is a saviour…… As are you guys!

(y)
 
Hi all,
Just to let you know that the issue with our Croma has been solved!!!

The problem was a broken wire that connects the Coolant Temperature Sensor to the Air Temperature Sensor.

(Incidentally, these two components both share an ‘earth’)

This fault meant that the ECU was receiving wrong readings from the Sensors……


(Cannot thank all of you guys enough for the phenomenal support!!!!!)


Our beloved Croma is purring like a kitten once again…..! :)
 
Hi all,
Just to let you know that the issue with our Croma has been solved!!!

The problem was a broken wire that connects the Coolant Temperature Sensor to the Air Temperature Sensor.

(Incidentally, these two components both share an ‘earth’)

This fault meant that the ECU was receiving wrong readings from the Sensors……


(Cannot thank all of you guys enough for the phenomenal support!!!!!)


Our beloved Croma is purring like a kitten once again…..! :)

Hi all,
I hope that someone can provide a bit of clarity on what the true meaning is here…..

On the ECU, there is a sticker that says:

THIS ECU REQUIRES ADAPTORS CODE 7626556 REMOVEMENT IF MOUNTED ON AIR/WATER SENSORS

Do you connect to the Air Sensor only?
Do you connect to the Water Sensor only?
Do you connect to both?

(The issue with our Croma is, unfortunately, still ongoing…. Because the fault is intermittent, means that it gives ‘false’ hope that the problem has been cured…. Before about ‘1 drive in twenty’ would be a ‘normal’ one. Now, every drive is ‘bad’……!!! At least the broken wire has been fixed, meaning that the engine no longer suddenly cuts out when the car hits a slight bump on the road).


Thanks!
 
The label shows a picture of the adaptor. Seems to suggest that if adaptors are fitted to the sensors, they should be removed if fitting that ECU.

If the ECU was already fitted to the car, then it's likely that the adaptors (if fitted), would already have been removed.
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The label shows a picture of the adaptor. Seems to suggest that if adaptors are fitted to the sensors, they should be removed if fitting that ECU.

If the ECU was already fitted to the car, then it's likely that the adaptors (if fitted), would already have been removed.
.
Hi,
Thank you very much for your rapid response. I will pass on the info to our mechanic……
 
Hi all,

Unfortunately, the starter motor for our Croma ie (1987) has just burnt out…..

(Issue with engine is still ongoing but has been deduced to just two or three things that it can be….. surely, must be down to something silly, as many of the components have been replaced with new ones….Bad terminal contact/broken wire somewhere?)

Anyway, our mechanic has tried to track down a new starter motor but has had no luck…..

Do you know where one can be bought?
Or
Do you know of any specialist company that can rebuild the existing starter motor?

As always, any support/advice much needed and appreciated!


(Thanks)
 
Hi Davren,

Thanks so much for your help…. So quick! I will E-mail our mechanic with the details right now…..

BRILLIANT!
Hi Davren,

Apologies for bothering you again but would it be possible for you to find out the Part No. for the Starter Motor?

(Our mechanic is really struggling, trying to find the right one….)

Here are the complete details:

1987 Fiat Croma 2.0 ie (super version)

VIN/Chassis/Frame No. ZFA15400000133948
Engine No. 0787357

On Vehicle (Placard)……

FIAT AUTO S.P.A.
02114T
ZFA 154000 00133948
Engine - 834B.000
Version - 154 AD55A


(Thanks)
 
Unfortunately, I don't have a Fiat parts catalogue for the 154 Croma. I found a Magneti Marelli catalogue online here:


It shows various part numbers for the 154 AD engine Croma starter motor. If you click on the light blue O.E. and trade part numbers, then on the small camera icon, it will show pictures of the motor, that you can compare with yours.
.
 
Unfortunately, I don't have a Fiat parts catalogue for the 154 Croma. I found a Magneti Marelli catalogue online here:


It shows various part numbers for the 154 AD engine Croma starter motor. If you click on the light blue O.E. and trade part numbers, then on the small camera icon, it will show pictures of the motor, that you can compare with yours.
.
Hi Davren,

Thank you for responding to me so quickly. Shame that you do not have the Product No. of the Starter Motor but the images may well help….

Here’s why – The original Motor was replaced about 25 years ago, by a ‘third-party’ one.

It may well be easier to track down an original. Anyway, not too worried about it, as the Starter Motor can be re-built, if need be…..

Very much appreciate the info!

Take care!
 
Hi Davren,

Thank you for responding to me so quickly. Shame that you do not have the Product No. of the Starter Motor but the images may well help….

Here’s why – The original Motor was replaced about 25 years ago, by a ‘third-party’ one.

It may well be easier to track down an original. Anyway, not too worried about it, as the Starter Motor can be re-built, if need be…..

Very much appreciate the info!

Take care!
Hi Davren,

Just to let you know that our mechanic has manage to locate a Starter Motor for our Croma and it is due to arrive in the middle of this coming week, from Germany. The housing is a recondition one but all of the internals will be brand new! It is a ‘win win’ situation, especially as the ‘Can’ on the motor is cracked; may be difficult to repair…..

You have gone to a lot of trouble for me Davren, and I am therefore very touched; great to get a ‘visual’ of what the original Starter Motor actually looks like.

(Only fair to keep you in the loop; hopefully, you have a smile on your face right now too….!)

Goes without saying that I will let all of you know how progress goes with the ‘ongoing’ lack of power issue; mechanic reduced it down to 2 or 3 things that it could be. (It is taking so long because he works on our car when he gets some spare time, which he finds hard to find….) Give a little back to the FIAT Community, so as to help any one else with this nightmare dilemma; hopefully pinpoint the problem straight away….


(Thanks again)
 
A little late to this.

Hope your arriving starter motor is correct.

The neared I could get was for a Croma 154.041. Year 1990-1992, 2 Litre CHT FL90 (from ePER)

P/N: 7589942 replaced by 46406474 in 20/10/1995

No guarantees on this info but suspect is pretty OK.
Hi,

very sorry for not replying sooner. Lost touch with my E-mails/FIAT Forum…… Thanks for the added info; always good to have as a future reference. The Starter Motor is the right one and is fitted. Still need to find the ‘pesky’ culprit but getting close…..
 
Hi all,
Just to let you know that, at last, the Croma issue has been solved…So much trouble trying to find the cause!

The work that has been done…..


Carry out extensive checking and testing for poor starting
and running. Locate engine control unit and plug in
breakout box to enable oscilloscope work.. study harness
data and rectify incorrect wiring population. Remove starter
motor due to disintegration of components locking engine.
Install new starter supplied. Carry out installation of rail
pressure gauges and check and test fuel components.
Rectify by installing new fuel pump with housing and new
pipe work as required.


Below is a revised full description of the symptoms, so that anyone with this unfortunate problem may be able to pinpoint it straight away…..

The issue is that the engine lacks any real power. At the best of times, the engine gives out less than half of what it is capable of producing. In the worst case, the car struggles to travel along, even on a level road, let alone any incline and takes time to gather any momentum. On start-up, the engine sounds very weak; choked up, as if the intake of air/fuel is lacking. It no longer sounds deep and ‘throaty’ like it should, when on idle. Also, the throttle does not seem as responsive as it once used to be…. If you ‘blip’ the accelerator (FIAT engines love to be revved by the way…), the engine does not like it at all. When revved a bit, the throttle also tends to stick at about 2000 rpm for a few seconds, before dropping back down to idle. The car also stutters/kangaroo jumps at times; lasting for a few seconds, before settling down once again. Under load, the engine just struggles to gain high revs; almost impossible to achieve slightly higher than 3000rpm.

In the worst case scenario, the engine starts to get more and more choked up, as if it is severely starved of air before stalling. Two different methods have been tried here when this happens (pumping and not pumping the throttle) but nothing works; the engine always stalls. (Incidentally, this tends to happen only when the engine reaches ‘working temperature’….). There is absolutely no point in trying to start the engine because it will either start up for a few seconds and then stall again or not start at all; persevering will just end up wrecking the starter motor! The best thing to do is to let the engine cool down for a few minutes. Opening the bonnet helps dissipate the heat faster, so as to help it to restart; some kind of heat-related problem seems to be happening here…..


Our Croma is a happy bunny once again!



Thanks for your support
 
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