1 have 1990 volvo 740gl b230f.if crank sensor is bad will i have spark to plugs. i have spark at plugs, but i dont get 12v at cps connector.put voltmeter on #1 terminal,and neg to ground,turn ign. to on position,got no reading.was this correct testing procedure? thanks

If you have strong, consistent spark at all plugs, then the CPS is likely doing its job.

I prefer to test for spark with a timing light - hook it up to #1 wire, pull the trigger and have someone crank the engine. The light should flash at consistent intervals that match the cranking speed.

Do you have a no-start? What are the circumstances that led you to suspect the CPS?

it is a no start.car would not crank.smelled like it was flooding.timing belt is new.checked and rechecked timing marks,(thought it had jumped timing).replaced radio relay,cleaned and checked throttle body,and switch.have fuel at regulator,new regulator,have 12v at injectors.321 code had been on for months,rough idle on start up.unplugged connector to cold start valve,still no start.now im down to cps,cold start valve,ect?,ecu? as i said in post,i did not get 12v at cps connection,if i tested it correctly,ign. on,lead to #3 terminal,neg to ground.any suggestions.thanks

With spark at the plugs, and assuming that it is strong and consistent, the next most likely suspect is fuel. 12v at the regulator means the RSR is working. But it doesn't mean that the injectors are firing.

The RSR supplies a constant 12V to the injectors. The ECU provides the ground that makes them fire. So try testing for that ground, by reversing the test - hook the pos side of a test light to a known 12 volt source, the neg side to the ground side an injector and crank the engine. If the light does not blink, you're not getting ground to the injectors and that points to the ECU. By any chance, do you have a pink label 561 ECU.

An easy test for failed fuel delivery is to spray some fuel like substance - starter fluid or carb cleaner works - directly into the throttle body. If the car starts momentarily, then dies, it's a fuel delivery problem.

If you have spark and fuel, it may be that you're not getting enough fuel. I had a similar situation a couple of years ago in and 89 740 - good spark, fuel at the rail, properly timed. Turned out to be both fuel pumps. The in tank had failed, and the primary pump wore itself out trying to make up for the missing prime provided by the in-tank.

You mention a new timing belt. Did the problem start immediately after the change, or after the plug wires were off for any other reason? Any chance you mixed up the ignition wires at the distributor? That's an easy mistake - the four straight-up posts on the cam driven cap setup are not 1-2-3-4 -- the order from left to right is 2-1-3-4.

If you are at the radiator facing the firewall. The 2 1 3 4 is from right to left, not left to right.

Firewall
4 3 1 2
Eng
4
3
2
1
Radiator
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Left, right, up, down - here's a picture

:)

http://www.brickboard.com/RWD/volvo/1315838/740/760/780/update.html

Courtesy of Lucid.

from top to bottom like your photo,my is 4312.my firing order is 1342,#1 is second terminal from right,looking from radiator.

thats what i have looking from radiator right to left,2134,first terminal on right is 2,1,3,4 is last om left.

Since you say you have good spark at the plugs, fuel into the cylinders, good compression. That leaves spark at the right time, or my next guess is plugged cat/exhaust system. I had similar, cat blew its guts and plugged exhaust where the pipe routes over the rear axle. I found this when a friend tried spraying starting fluid into the intake and mentioned it didn't seem to being drawing any in. If it was mine, I would put a timing light on it and see what the marks are doing at the crank pulley. Any chance sheared pin on cam pulley?
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"i did not get 12v at cps connection,if i tested it correctly,ign. on,lead to #3 terminal,neg to ground."

There is no voltage at the CPS connection until the sensor generates the signal to the EZK ICU. But as others have said, if you have spark at the plugs, the CPS must be working.

Below is a sequenced list of the main steps for starting and running:

Start-Run Sequence LH2.4 or REX

1) During starter cranking, the Crank Position Sensor sends timing pulses to Ignition Control Unit (ICU = EZK or REX)

2-a) The ICU uses these CPS pulses to trigger the Power Stage (aka Ignition Amplifier), which initiates spark from the coil.

2-b) At the same time, The ICU also propagates the pulses to the FI ECU, to allow FI operation (no ICU pulses means no FI operation).

3-a) The Fuel Injection (System)* relay (previously energized at Key On) powers the AMM, IAC, ECU, Injectors, and Fuel (pump) relay coil + side.
* The System relay is in the white case with the Fuel relay.

3-b) When ICU pulses are received by the FI ECU, it "energizes" the Fuel relay by grounding the relay coil (– side) to run the fuel pumps.

When all these things work, the engine runs until the Ignition is switched off, which in turn shuts down the FI system.

Determining whether or not there is spark at the plugs (2a) — and whether or not the plugs are getting gas (3b) — makes a good no-start "starting" point.

For example, if 2a fails due to a bad Power Stage/Amplifier, there will be a no-start with gas-wet plugs. If 2b fails (practically never) symptoms will be Fuel-related: a no-start with spark at the plugs, but plugs remain dry.
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Bruce Young, '93 940-NA (current), 240s (one V8), 140s, 122s, since '63.

I don't know why there's no 'thumbs up' option on all the posts in this thread except the top one.
This one deserves it, and IMO, printing out the above and keeping it in the car next to other vital papers will save some of us a lot of time and money.

Weird; different browser, now I can give credit where it's due. Thanks Bruce.

i quess theres no thumbs up,because car still wont crank.if i get post that gets car running,i will say that answered my question,and solved promblem.

I think I suggested that back in that CSV thread, when it seemed like you were getting fuel injected (noid light flashing) but not burning it.

That condition has been known to cause a no-start due to low compression caused by unburnt fuel washing down cylinder wall and rings.

checked compression this morning(in case flooding washed oil off cyls.)i have over 150 on all cyls.

http://www.brickboard.com/FAQ/700-900/EngineSensors.htm#Crank_Postition_Sensor
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i have faq downloaded.does not mention spark to plugs.it tells you to crank car over when testing volts to cps.service manual,and other sites says to just turn ign. on to test.if there should be no spark to plugs if cps is bad,then im getting ready to spend money on part that is not bad.as you can tell allekat,i still dont have car cranked.

Without a cranking signal,ie sensor, no spark at plugs. Backtrace and see if your getting 12volts to the coil.
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i am getting 12v at blue wire and red/white wire.