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87 comanche 2.5 spark but no power to injector


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i recently put a motor out of am 86 into my 87 cause the motor went due to unkown reason. i swpapped off of my old motor including valve cover, intake and the exhaust manifold.

today i finshed hooking everything up , i made sure i connected all my grounds, all conections except for two small air hoses that broke 1 to tb and other to tb boot. before i swapped the motor the truck ran. well i tried startin and it would just crank and crank and crank but no start.

i put an injector pulse light on the single injector in the tb and it didnt light. so i poured a little gas down the tb and it fire right up. the cps wasnt damaged durin the proces to my knowledge but someone that was helping had a prybar in that area and broke my 02 sensor so he may have hit it but he didnt tell me. and does the cps eveng give power to the injector. and i disconected both fuel lines at tb 1 at a time and no fuel came out of either when i tried priming. any suggestions.

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okay update: i swapped the fuel pump relay with the one next to it and it fired right up, but the motor has a constant miss, feels like its outa time and the dizzy bolt was loose. i think someone pulled out the dizzy and put it back in wrong or somethin. i am getting frustrated with this comanche. is there a technique to re-align a dizzy , i am an advancing oil changer and some of this stuff is getting outa my reach. when it first started up it ran horrible it had a crossed wire and a plug with carbon in the gap. so i fixed that, ran better, then i replaced the coolant temp sens. and o2 sens, and it ran like normal for a quick 2-5 second than back to normal.

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the dizzy is not adjustable....adjusting it messes with the fuel delivery somehow, but doesn't actually change the timing.. in order to make sure that it's set right, you need to bring the #1 cylinder to TDC (top dead center) on the compression stroke. to do this you pull the #1 spark plug out and pull the coil wire off so it doesnt start, and using a remote start switch or a buddy inside the truck, crank the engine while holding your finger in the plug hole, and when it blows your finger out of the hole, stop cranking and then turn the crank damper with a wrench until the 0 mark on the damper lines up with the pointer on the engine... then pull the cap off and see where the rotor is pointed, if it's not pointed at the #1 wire terminal adjust it so it is....

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all is well now, i solved the problem. really i should have done it to begin with but it was those 2 air lines i broke 1 was the map sensor line and the other was egr to tb. i rellaced those and started it up and it ran great, then i took it on a test drive and it rode great then started back firing and bogging then it came through itt, i put fresh gas in , figured thatd be it since it had been sitting for 3 months. did that and it feels like the cat is clogged. and it makes sense. i need to get the right relay for the fuel pump and get a new cat put on and the truck will be like new again i hope. but i idles very smothly and drives very smooth even though it accelerates so slow.

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and the cat wasnt clogget, the tps was fried. it had 5volts goin to it and no power to the reference wire to the pcm so i replaced the tps and it feels great. now i just need to replace my cardboard tb gasket and put another valve cover gasket as it seems i may have overtightened it and it pushed out the gasket so it starts smokin under the hood at idle

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thanks, i did back when i started the account, but i sold it, it was an 84 with amg spoilers and it was a 5 speed but it had the 8 valve 2.3 not the great 16 valve but it was still a very fun car and noone knew it was an 84

 

Yea, great cars. Have had many W201s and W124s, but all were 6-cylinders. Always wanted a W124 500E. :drool:

 

mercedes_500e_w1241.jpg

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