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Volvo 245 no spark

Volvotazz

New member
Joined
Mar 17, 2020
what damage would reversed coil wires do.
They should be 2 blue to + and 2 red/white to -.
But they where not and have damaged something
What damage would it cause if were 1blue, red/white to + and 1blue, red/white to -.

No spark. Have changed to correct blue +, R/W -
No fuses are blown but have no spark and need to trace back why and where.
New ICU and ECU but still same. What and how should I check?
Volvo 2.0ltr 1993 lh 2.4
Bosch 0227 400 176 ICU
Jetronic 0280000949 ECU

Initial problem started in March 2020.
Car drove to MOT test centre fine for test, but won't start for technician.
They tried a few things and tested a few theories ( this i think resulted in someone putting back wires on coil wrong way round)
Every ignition part changed at least once to new or (volvo 2nd parts as new not available)but nothing made engine run right. code 121 all the time. Wiring continuie checked by auto electrican, last major component changed ECU( had circuit board cracked). Then engine ran but differently. No code 121 anymore
Engine rang 30 sec (rough) then stopped , no spark. Wiring checked again for continuie (then COIL reversed wires error picked up on wiring diagram.)
2nd hand ECU AND ICU FITTED BUT STILL NO SPARK.
Fuel pump relay swapped no spark
MAF swapped still no spark
Coil amplifier swapped , SPARK ( engine tries to run but seriously rough and dies)
Engine now has code 121 (yes Maf however fault ECU will also create this code)

So what components do I risk next, MAF , ECU or ICU
 
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You most likely have a bad ignition power amplifier (also called an ignition module). For LH2.4, it should be a Bosch 0 227 100 124, and is mounted on the fender.

The blue wires are +12volts from the ignition switch. One red/white wire comes from the power amplifier - it's grounded by the amplifier to charge the coil. The other red/white wire goes to the tach (if present). Connecting blue directly to red/white will cause the amplifier to quickly overheat and fail when it tries to ground +12volts from the ignition switch.

The ignition module bolts to an aluminum block that's screwed to the fender. When replacing the module, you should add a dab of heat sink compound (the messy white grease) between the module and the aluminum block.
 
update on progress

In addition to above missed info and new info

Initial problem started in March 2020.
Every ignition part changed at least once to new or (volvo 2nd parts as new not available)but nothing made engine run right.
☆ CODE 121 ALL THE TIME
Wiring continuie checked by auto electrican, last major component changed ECU( had circuit board cracked). Then engine ran but differently.
☆ NO CODE 121 ANYMORE
Engine rang 30 sec (rough) then stopped , no spark. Wiring checked again for continuie (then COIL reversed wires error picked up on wiring diagram.)
☆ TODAY TASK BELOW
2nd hand ECU AND ICU FITTED BUT STILL NO SPARK.
Fuel pump relay swapped no spark
MAF swapped still no spark
Coil amplifier swapped , SPARK ( engine tries to run but seriously rough and dies)
Engine now has code 121 AGAIN (yes possible Maf [not wiring as auto electrican checked previous]
however fault ECU or ICU will also create this code NOT SURE WHICH)

ANY ADVICE I SPENT ?600 or so in parts etc and not sure whats good or bad plus welding to do also.!
So what components do I risk next, MAF , ECU or ICU
 
tomorrow jobs

Swap out CPS for old and see if runs better.

Swap MAF to another see if removes 121 code

if no change
Then its either swap ICU OR ECU

As previously I think POSSIBLE FAULTY ECU would give a 121 code instead of faulty ICU
FAULTY ICU won't allow engine to want to run or would it ?

Again any advise welcome this has been a 8 month battle.
 
What u mean by scope? Don't have access to oscilope.!
Checked compression in March ETC was good
Checked inject spray and all was equal.
Timing was BANG on
 
swapped everything I said I would and nothing
However the injectors are not getting signal.
I put a node light on and nothing when cranked over.
There is spark in plugs ( inline tester confirmed) lack of spark confirmed by faulty amplifier

So what controls the injector pulse.
Is there a relay ( RSR )radio suppression relay or is this on new 740/940.
And if there is where . Many thanks in advance I feel like I'm so close.
 
Injectors disconnected and plugs cleaned (air blown dry)
Engine runs breifly.with carb cleaner sprayed into throttle body with injectors disconnected.
Fuel rail is pressurised and fills at 100ml per sec into bottle (but not opened relay to check inside) as swapped as have 3 still no difference
Injectors have no power.
Have 3 CPS tried each made no difference. But not back probed YET( but will just to be 100% sure)
Wiring is good on car as auto electrican checked for continuie .
I ask.
The injectors are controlled by Jetronic which runs through the fuel pump relay or different relay to get injectors ? Y/N
 
You also don't know if one of these "electricians" have damaged your electrical terminals by stuffing the incorrect test probes into the terminals.


Does the engine STAY RUNNING if you PULSE brake cleaner into the throttle?? I can run a 6.2L truck on a can of brake cleaner.

No power to the injectors!!? That's a problem! The injectors are not POWERED from the LH Box. They are low side (ground) controlled by the LH BOX. If you don't have POWER to the injectors you need a wiring diagram and a test lamp then do basic circuit diag.


HERE YA GO!! It looks like the power for the injectors comes right off the EFI/"fuel pump" relay. It looks like it also powers the MAF. Is your MAF powered up??? In this diagram, it is an ORANGE wire. (yours could be different)

Right click links and open in a new tab to view!!


lh24.jpg



1990-240-ezk.png
 
I got the green book and Haynes manual UK Only difference is no cold start valve (think is an American thing)
Auto electrican was independent specialist who identified ECU . He didn't remove components.

It could be fuel pump relay ( fuel pressure could just be from intank pumps alone and not pump)
The relays could be damaged when testing engine when coil wires wrong .
Icu and ecu were new after coil issue so don't think is them.

Engine won't run long enough to respray carb cleaner as on own in shed.

I order a new relay, but will open old relay and check working
 
At breaking point

FFS.
Yesterday noid light did nothing when cranked engine over.
So pulled injector off head and cranked engine they all fired fine. Spraying fuel.
Engine tries to run on carb cleaner with no fuel supplied, but barely and not long enough for me to respray more in [on my own]
Fuel relays work fine removed cover on all 3 as stated in instructions each section of relay work
MAF
E10 pin 6 and7 ECU has 2.5 to 4 ohms
E13 pin5 on maf has no power
Same reading on 4 other mafs.

CPS HAS 200ohms
But no V on AC when cranked on 2pin
Tried 2 CPS both the same results

Feel like I'm going round in circle chasing my tail. I don't mind spending money on parts but on what.
A new ECU AND ICU went on after the coil error identified but still nothing that result narrowed it down to amplifier that got swapped.
What have I missed
 
It sounds like you have had at least 2 or 3 different issues:
- stopped running at MOT
- cracked ECU board
- damaged ignition amplifier due to blue and red/wt wires being connected at the coil

Was the car running fine prior to MOT, or had other repairs been completed recently?

Any ignition amplifier that you had installed with the crossed wires is now bad (no spark) or damaged (weak/intermittent spark).

Look in the greenbook on the Starting Circuit page and find the starter motor service terminal (Pink wire) in the engine bay. If you jumper this to battery +12, it will crank the starter, and will try to start if the key is on. You can use this so that you can spray spurts of carb cleaner immediately after cranking.

The CPS goes to the ICU. A bad CPS will result in no spark. If you have a timing light, you can check timing while cranking/trying to run. If you have spark and the timing is good, the issue is most likely fueling. After trying to start, are there any code posted?
 
Engine running. Sort of

OK got the engine to run, eventually.
Seriously hard to start.
Disconnected fuel but Would not run on carb cleaner just kept backfiring and burning my hand.
Disconnected fuel, dried plugs and cranked ignition to remove excess fuel , with ignition left on reconnected fuel ,2 sprays of carbcleaner and cranked starter via pink wire. (No MAF CONNECTED I removed it earlier to see if could start in limp mode)
Engine ran but struggled to idle, no popping or bang and managed to get some good rev on it.
It idled on its own but very laboured of course, Code 121 and 311 obviously 121 not having MAF. 311 signal missing from speedometer?
Obviously it would not rev high etc and
Switched off and tried to started it again about 2hrs later this time with Maf in but think battery had enough.
So will try again tomorrow same way but with MAF.

PICKED UP TEST LAMP ALSO.
 
Good, sounds like CPS and ignition are working fine and you're on to chasing fueling issues.

Before doing much else, I'd check the fuel pumps. The easy test is to jumper the fuel pump fuse, I think it's #4 on your 93, to +12v (fuses 7,8,9,10 on 93?), and listen to the under car pump and to the in tank pump (remove the gas cap) to make sure they sound OK. If you're not sure, you can pull fuse #4 and jumper one side at a time to run one pump at a time.
 
Look at your wiring diagram and determine which fuse gets power, key on, from the fuel pump relay. You could also do your testing right at the relay.


Key on, test lamp to MAF power wire to ground. Illuminate?
 
Last steps and so grateful

please could I ask you to before specific on instructions, Sorry I'm very dyslexic and a little lost
 
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